<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Publishing DTD v1.3 20210610//EN" "JATS-journalpublishing1-3.dtd">
<article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" article-type="research-article" dtd-version="1.3" xml:lang="en">
  <front>
    <journal-meta>
      <journal-id journal-id-type="publisher-id">Ecological Safety of Coastal and Shelf Zones of Sea</journal-id>
      <journal-title-group>
        <journal-title xml:lang="en">Ecological Safety of Coastal and Shelf Zones of Sea</journal-title>
        <trans-title-group xml:lang="ru">
          <trans-title>Экологическая безопасность прибрежной и шельфовой зон моря</trans-title>
        </trans-title-group>
      </journal-title-group>
      <issn publication-format="print">2413-5577</issn>
    </journal-meta>
    <article-meta>
      <article-id pub-id-type="publisher-id">20250308</article-id>
      <article-id pub-id-type="edn">UVGARW</article-id>
      
      <article-categories>
        <subj-group subj-group-type="toc-heading" xml:lang="ru">
          <subject>Научная статья</subject>
        </subj-group>
        <subj-group subj-group-type="article-type">
          <subject>Research Article</subject>
        </subj-group>
      </article-categories>

      <title-group>
        <article-title xml:lang="en">Wave Buoy Logger for Coastal Studies</article-title>
        <trans-title-group xml:lang="ru">
          <trans-title>Волноизмерительный буй-логгер для прибрежных исследований</trans-title>
        </trans-title-group>
      </title-group>

      <contrib-group>
        <contrib contrib-type="author">
          <name-alternatives>
            <name xml:lang="en">
              <surname>Yurovsky</surname>
              <given-names>Yu. Yu.</given-names>
            </name>
            <name xml:lang="ru">
              <surname>Юровский</surname>
              <given-names>Ю. Ю.</given-names>
            </name>
          </name-alternatives>
          <email>y.yurovsky@mhi-ras.ru</email>
          <xref ref-type="aff" rid="aff1"/>
        </contrib>
        <contrib contrib-type="author">
          <name-alternatives>
            <name xml:lang="en">
              <surname>Kudinov</surname>
              <given-names>O. B.</given-names>
            </name>
            <name xml:lang="ru">
              <surname>Кудинов</surname>
              <given-names>О. Б.</given-names>
            </name>
          </name-alternatives>
          <email>obk91@mail.ru</email>
          <xref ref-type="aff" rid="aff1"/>
        </contrib>
      </contrib-group>

      <aff-alternatives id="aff1">
        <aff xml:lang="en">
          <institution>Marine Hydrophysical Institute of RAS</institution>
          <addr-line>Sevastopol</addr-line>
          <country>Russia</country>
        </aff>
        <aff xml:lang="ru">
          <institution>Морской гидрофизический институт РАН</institution>
          <addr-line>Севастополь</addr-line>
          <country>Россия</country>
        </aff>
      </aff-alternatives>

      <pub-date date-type="pub" iso-8601-date="2025-09-30" publication-format="electronic">
        <day>30</day>
        <month>09</month>
        <year>2025</year>
      </pub-date>
      <issue>3</issue>
      <fpage>115</fpage>
      <lpage>127</lpage>

      <history>
        <date date-type="received" iso-8601-date="2024-12-09">
          <day>09</day>
          <month>12</month>
          <year>2024</year>
        </date>
        <date date-type="rev-recd" iso-8601-date="2025-01-21">
          <day>21</day>
          <month>01</month>
          <year>2025</year>
        </date>
        <date date-type="accepted" iso-8601-date="2025-06-24">
          <day>24</day>
          <month>06</month>
          <year>2025</year>
        </date>
      </history>

      <permissions>
        <copyright-statement xml:lang="en">Copyright ©; 2025, Yurovsky Yu.Yu., Kudinov O.B.</copyright-statement>
        <copyright-statement xml:lang="ru">Copyright ©; 2025, Юровский Ю.Ю., Кудинов О.Б.</copyright-statement>
        <copyright-year>2025</copyright-year>
        <copyright-holder xml:lang="en">Yurovsky Yu.Yu., Kudinov O.B.</copyright-holder>
        <copyright-holder xml:lang="ru">Юровский Ю.Ю., Кудинов О.Б.</copyright-holder>
        <ali:free_to_read xmlns:ali="http://www.niso.org/schemas/ali/1.0/"/>
        <license>
          <ali:license_ref xmlns:ali="http://www.niso.org/schemas/ali/1.0/">https://creativecommons.org/licenses/by-nc/4.0/</ali:license_ref>
        </license>
      </permissions>
      <self-uri xlink:href="https://ecological-safety.ru/repository/issues/2025/03/08/" xlink:title="Страница статьи">https://ecological-safety.ru/repository/issues/2025/03/08/</self-uri>
      
      <abstract xml:lang="en">
        <p>The paper presents prototype wave buoy loggers designed to collect raw data from a built-in inertial motion unit without transmitting the data to the user. These buoys require maintenance but have a significantly simpler design and much lower cost compared to unattended analogs, making them particularly useful for various coastal studies. The study aims to demonstrate that measuring wave parameters in field conditions with acceptable accuracy is achievable without loss of data quality. The buoys were tested in a field experiment at the Black Sea Hydrophysical Sub-Satellite Polygon of Marine Hydrophysical Institute, Russian Academy of Sciences. Reference measurements were obtained using wire wave gauges installed on the Stationary Oceanographic Platform (44.393047°N, 33.984596°E). Three identical buoys were deployed near the platform using different mooring configurations: a heavy anchor with an elastic insert (rubber cord), a heavy anchor without an elastic insert, and a buoy suspended directly from the platform without an anchor. Continuous measurements were conducted over seven days, during which significant wave height varied from 0.2 to 1 m, and wind speeds ranged from 0 to 15 m/s, coming from easterly, westerly, and northerly directions. Under these conditions, the root-mean-square error in estimating significant wave height was no more than 5–6 cm (both with and without the rubber cord), with the linear regression coefficient deviating from 1 by less than 5%. The root-mean-square errors for the spectral peak wave period and direction were 0.37–0.62 s and 50–65°, respectively. These errors are comparable to the resolution of the applied methods and the natural statistical variability of wave parameter estimates.</p>
      </abstract>
      
      <trans-abstract xml:lang="ru">
        <p>Представлены прототипы волноизмерительных буев-логгеров, предназначенных для сбора исходных данных со встроенных в эти буи инерциальных датчиков без передачи информации на берег. Буи такого типа нуждаются в обслуживании, но имеют существенно более простую конструкцию и низкую стоимость по сравнению с необслуживаемыми аналогами, что может быть востребовано в различных прибрежных исследованиях. Цель работы – продемонстрировать в натурных условиях, что предлагаемый тип буев может эффективно использоваться для измерения характеристик волнения без потери качества данных. Испытания буев проведены в натурном эксперименте на Черноморском гидрофизическом подспутниковом полигоне Морского гидрофизического института РАН. В качестве референтной информации о волнах использованы данные измерений струнными волнографами, установленными на стационарной океанографической платформе (44.393047° с. ш., 33.984596° в. д.). Три одинаковых буя были установлены вблизи платформы с использованием разных вариантов удерживающего устройства: на массивном якоре с эластичной вставкой (амортизатором) и без нее, а также без якоря на подвесе с платформы. Непрерывные измерения велись в течение 7 сут, в течение которых высота значительных волн менялась от 0.2 до 1 м, скорость ветра от 0 до 15 м/с при его восточном, западном, северном направлениях. В этих условиях среднеквадратичная ошибка оценки высоты значительных волн составила не более 5–6 см (с амортизатором и без него) при отклонении коэффициента линейной регрессии от единицы не более чем на 5 %. Среднеквадратичные ошибки периода и направления волн спектрального пика составили 0.37–0.62 с и 50–65° соответственно при измерении буем с амортизатором и без него. Такие ошибки измерений сопоставимы с разрешающей способностью используемых методов и естественным статистическим разбросом средних оценок параметров волн.</p>
      </trans-abstract>

      <kwd-group xml:lang="en">
        <kwd>buoy</kwd>
        <kwd>wave gauge</kwd>
        <kwd>inertial measurements</kwd>
        <kwd>wind waves</kwd>
        <kwd>wave parameters</kwd>
        <kwd>oceanographic platform</kwd>
        <kwd>field experiment</kwd>
      </kwd-group>
      <kwd-group xml:lang="ru">
        <kwd>буй</kwd>
        <kwd>волнограф</kwd>
        <kwd>инерциальные измерения</kwd>
        <kwd>ветровые волны</kwd>
        <kwd>параметры волн</kwd>
        <kwd>океанографическая платформа</kwd>
        <kwd>натурный эксперимент</kwd>
      </kwd-group>

      <funding-group>
        <funding-statement xml:lang="en">The work was funded by the Russian Scientific Foundation grant 24-27-00153 "Measuring waves with small buoys: methods, validation, prospects of miniaturization".</funding-statement>
        <funding-statement xml:lang="ru">Работа выполнена при финансовой поддержке гранта Российского научного фонда № 24-27-00153 «Волнографические измерения с помощью малогабаритных буев: методология, валидация, перспективы миниатюризации».</funding-statement>
      </funding-group>
    </article-meta>
  </front>

  <body>
    <p>Текст статьи не включен.</p>
  </body>

  <back>
    <ref-list>
      <title>Список литературы</title>
      <ref id="B1">
        <label>1.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Kuznetsov</surname><given-names>S.</given-names></name>
            <name><surname>Saprykina</surname><given-names>Y.</given-names></name>
          </person-group>
          <article-title>Nonlinear wave transformation in coastal zone: free and bound waves</article-title>
          <source>Fluids</source>
          <year>2021</year>
          <volume>6</volume>
          <issue>10</issue>
          <fpage>347</fpage>
          <pub-id pub-id-type="doi">10.3390/fluids6100347</pub-id>
        </element-citation>
      </ref>
      <ref id="B2">
        <label>2.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Brown</surname><given-names>A.C.</given-names></name>
            <name><surname>Paasch</surname><given-names>R.K.</given-names></name>
          </person-group>
          <article-title>The accelerations of a wave measurement buoy impacted by breaking waves in the surf zone</article-title>
          <source>Journal of Marine Science and Engineering</source>
          <year>2021</year>
          <volume>9</volume>
          <issue>2</issue>
          <fpage>214</fpage>
          <pub-id pub-id-type="doi">10.3390/jmse9020214</pub-id>
        </element-citation>
      </ref>
      <ref id="B3">
        <label>3.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Masson</surname><given-names>D.</given-names></name>
          </person-group>
          <article-title>A case study of wave-current interaction in a strong tidal current</article-title>
          <source>Journal of Physical Oceanography</source>
          <year>1996</year>
          <volume>26</volume>
          <issue>3</issue>
          <fpage>359</fpage>
          <lpage>372</lpage>
          <pub-id pub-id-type="doi">10.1175/1520-0485(1996)026<0359:ACSOWI>2.0.CO;2</pub-id>
        </element-citation>
      </ref>
      <ref id="B4">
        <label>4.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Горячкин</surname><given-names>Ю.Н.</given-names></name>
            <name><surname>Удовик</surname><given-names>В.Ф.</given-names></name>
            <name><surname>Харитонова</surname><given-names>Л.В.</given-names></name>
          </person-group>
          <article-title>Оценки параметров потока наносов у западного берега Бакальской косы при прохождении сильных штормов в 2007 году</article-title>
          <source>Морской гидрофизический журнал</source>
          <year>2010</year>
          <issue>5</issue>
          <fpage>42</fpage>
          <lpage>51</lpage>
          <pub-id pub-id-type="other">TOERXH</pub-id>
        </element-citation>
      </ref>
      <ref id="B5">
        <label>5.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Saprykina</surname><given-names>Y.V.</given-names></name>
            <name><surname>Samiksha</surname><given-names>S.V.</given-names></name>
            <name><surname>Kuznetsov</surname><given-names>S.Yu.</given-names></name>
          </person-group>
          <article-title>Wave climate variability and occurrence of mudbanks along the southwest coast of India</article-title>
          <source>Frontiers in Marine Science</source>
          <year>2021</year>
          <volume>8</volume>
          <fpage>671379</fpage>
          <pub-id pub-id-type="doi">10.3389/fmars.2021.671379</pub-id>
        </element-citation>
      </ref>
      <ref id="B6">
        <label>6.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Andreeva</surname><given-names>N.</given-names></name>
            <name><surname>Saprykina</surname><given-names>Y.</given-names></name>
            <name><surname>Valchev</surname><given-names>N.</given-names></name>
            <name><surname>Andreeva</surname><given-names>T.</given-names></name>
            <etal/>
          </person-group>
          <article-title>Influence of wave climate on intra and inter-annual nearshore bar dynamics for a sandy beach</article-title>
          <source>Geosciences</source>
          <year>2021</year>
          <volume>11</volume>
          <issue>5</issue>
          <fpage>206</fpage>
          <pub-id pub-id-type="doi">10.3390/geosciences11050206</pub-id>
        </element-citation>
      </ref>
      <ref id="B7">
        <label>7.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Горячкин</surname><given-names>Ю.Н.</given-names></name>
            <name><surname>Косьян</surname><given-names>Р.Д.</given-names></name>
          </person-group>
          <article-title>Образование нового острова у берегов Крыма</article-title>
          <source>Океанология</source>
          <year>2020</year>
          <volume>60</volume>
          <issue>2</issue>
          <fpage>323</fpage>
          <lpage>330</lpage>
          <pub-id pub-id-type="other">PGHSZT</pub-id>
          <pub-id pub-id-type="doi">10.31857/S0030157420020033</pub-id>
        </element-citation>
      </ref>
      <ref id="B8">
        <label>8.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Zhou</surname><given-names>Y.</given-names></name>
            <name><surname>Liu</surname><given-names>J.</given-names></name>
            <name><surname>Zhu</surname><given-names>Y.</given-names></name>
            <name><surname>Song</surname><given-names>D.</given-names></name>
            <etal/>
          </person-group>
          <article-title>Influence of beach erosion during wave action in designed artificial sandy beach using XBeach model: profiles and shoreline</article-title>
          <source>Journal of Marine Science and Engineering</source>
          <year>2023</year>
          <volume>11</volume>
          <issue>5</issue>
          <fpage>984</fpage>
          <pub-id pub-id-type="doi">10.3390/jmse11050984</pub-id>
        </element-citation>
      </ref>
      <ref id="B9">
        <label>9.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Shimura</surname><given-names>T.</given-names></name>
            <name><surname>Kawamura</surname><given-names>H.</given-names></name>
            <name><surname>Katsumata</surname><given-names>K.</given-names></name>
            <name><surname>Kawamata</surname><given-names>S.</given-names></name>
            <etal/>
          </person-group>
          <article-title>Ocean surface wind estimation from waves based on small GPS buoy observations in a bay and the open ocean</article-title>
          <source>Journal of Geophysical Research: Oceans</source>
          <year>2022</year>
          <volume>127</volume>
          <issue>9</issue>
          <fpage>e2022JC018786</fpage>
          <pub-id pub-id-type="doi">10.1029/2022jc018786</pub-id>
        </element-citation>
      </ref>
      <ref id="B10">
        <label>10.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Дивинский</surname><given-names>Б.В.</given-names></name>
            <name><surname>Куклев</surname><given-names>С.Б.</given-names></name>
          </person-group>
          <article-title>Эксперимент по исследованию параметров ветрового волнения на шельфе Черного моря</article-title>
          <source>Океанология</source>
          <year>2022</year>
          <volume>62</volume>
          <issue>1</issue>
          <fpage>14</fpage>
          <lpage>19</lpage>
          <pub-id pub-id-type="other">UWBPIX</pub-id>
          <pub-id pub-id-type="doi">10.31857/S003015742201004X</pub-id>
        </element-citation>
      </ref>
      <ref id="B11">
        <label>11.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Rainville</surname><given-names>E.</given-names></name>
            <name><surname>Thomson</surname><given-names>J.</given-names></name>
            <name><surname>Deane</surname><given-names>G.B.</given-names></name>
            <name><surname>Van Uffelen</surname><given-names>L.</given-names></name>
            <etal/>
          </person-group>
          <article-title>Measurements of nearshore ocean-surface kinematics through coherent arrays of free-drifting buoys</article-title>
          <source>Earth System Science Data</source>
          <year>2023</year>
          <volume>15</volume>
          <issue>11</issue>
          <fpage>5135</fpage>
          <lpage>5151</lpage>
          <pub-id pub-id-type="doi">10.5194/essd-15-5135-2023</pub-id>
        </element-citation>
      </ref>
      <ref id="B12">
        <label>12.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Kinsela</surname><given-names>M.A.</given-names></name>
            <name><surname>Harley</surname><given-names>M.D.</given-names></name>
            <name><surname>Mortlock</surname><given-names>T.R.</given-names></name>
            <name><surname>Power</surname><given-names>H.E.</given-names></name>
            <etal/>
          </person-group>
          <article-title>Nearshore wave buoy data from southeastern Australia for coastal research and management</article-title>
          <source>Scientific Data</source>
          <year>2024</year>
          <volume>11</volume>
          <issue>1</issue>
          <fpage>190</fpage>
          <pub-id pub-id-type="doi">10.1038/s41597-023-02865-x</pub-id>
        </element-citation>
      </ref>
      <ref id="B13">
        <label>13.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Veras Guimarães</surname><given-names>P.</given-names></name>
            <name><surname>Ardhuin</surname><given-names>F.</given-names></name>
            <name><surname>Bergamasco</surname><given-names>F.</given-names></name>
            <name><surname>Le Boyer</surname><given-names>A.</given-names></name>
            <etal/>
          </person-group>
          <article-title>A surface kinematics buoy (SKIB) for wave-current interaction studies</article-title>
          <source>Ocean Science</source>
          <year>2018</year>
          <volume>14</volume>
          <issue>6</issue>
          <fpage>1449</fpage>
          <lpage>1460</lpage>
          <pub-id pub-id-type="doi">10.5194/os-14-1449-2018</pub-id>
        </element-citation>
      </ref>
      <ref id="B14">
        <label>14.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Yurovsky</surname><given-names>Yu.Yu.</given-names></name>
            <name><surname>Dulov</surname><given-names>V.A.</given-names></name>
          </person-group>
          <article-title>MEMS-based wave buoy: Towards short wind-wave sensing</article-title>
          <source>Ocean Engineering</source>
          <year>2020</year>
          <volume>217</volume>
          <fpage>108043</fpage>
          <pub-id pub-id-type="doi">10.1016/j.oceaneng.2020.108043</pub-id>
        </element-citation>
      </ref>
      <ref id="B15">
        <label>15.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Rabault</surname><given-names>J.</given-names></name>
            <name><surname>Nose</surname><given-names>T.</given-names></name>
            <name><surname>Hope</surname><given-names>G.</given-names></name>
            <name><surname>Müller</surname><given-names>M.</given-names></name>
            <etal/>
          </person-group>
          <article-title>OpenMetBuoy-v2021: an easy-to-build, affordable, customizable, open-source instrument for oceanographic measurements of drift and waves in sea ice and the open ocean</article-title>
          <source>Geosciences</source>
          <year>2022</year>
          <volume>12</volume>
          <issue>3</issue>
          <fpage>110</fpage>
          <pub-id pub-id-type="doi">10.3390/geosciences12030110</pub-id>
        </element-citation>
      </ref>
      <ref id="B16">
        <label>16.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Feddersen</surname><given-names>F.</given-names></name>
            <name><surname>Giddings</surname><given-names>S.N.</given-names></name>
            <name><surname>Thomas</surname><given-names>J.</given-names></name>
            <name><surname>Dauhajre</surname><given-names>D.P.</given-names></name>
            <etal/>
          </person-group>
          <article-title>The wavedrifter: a low-cost IMU-based Lagrangian drifter to observe steepening and overturning of surface gravity waves and the transition to turbulence</article-title>
          <source>Coastal Engineering Journal</source>
          <year>2024</year>
          <volume>66</volume>
          <issue>1</issue>
          <fpage>44</fpage>
          <lpage>57</lpage>
          <pub-id pub-id-type="doi">10.1080/21664250.2023.2238949</pub-id>
        </element-citation>
      </ref>
      <ref id="B17">
        <label>17.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Joosten</surname><given-names>H.</given-names></name>
          </person-group>
          <article-title>Directional wave buoys and their elastic mooring</article-title>
          <source>International Ocean Systems</source>
          <year>2006</year>
          <volume>10</volume>
          <issue>4</issue>
          <fpage>18</fpage>
          <lpage>21</lpage>
        </element-citation>
      </ref>
      <ref id="B18">
        <label>18.</label>
        <element-citation publication-type="conf-proc">
          <person-group person-group-type="author">
            <name><surname>Yurovsky</surname><given-names>Yu.Yu.</given-names></name>
            <name><surname>Dulov</surname><given-names>V.A.</given-names></name>
          </person-group>
          <article-title>Compact low-cost Arduino-based buoy for sea surface wave measurements</article-title>
          <source>Proceedings of Progress in Electromagnetic Research Symposium – Fall (PIERS – FALL), 19–22 November 2017. Singapore</source>
          <publisher-name>IEEE</publisher-name>
          <year>2017</year>
          <fpage>2315</fpage>
          <lpage>2322</lpage>
          <pub-id pub-id-type="doi">10.1109/PIERS-FALL.2017.8293523</pub-id>
        </element-citation>
      </ref>
      <ref id="B19">
        <label>19.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Бондур</surname><given-names>В.Г.</given-names></name>
            <name><surname>Дулов</surname><given-names>В.А.</given-names></name>
            <name><surname>Мурлыкин</surname><given-names>А.А.</given-names></name>
            <name><surname>Юровская</surname><given-names>М.В.</given-names></name>
            <etal/>
          </person-group>
          <article-title>Исследование спектров морского волнения в широком диапазоне длин волн по спутниковым и контактным данным</article-title>
          <source>Исследование Земли из космоса</source>
          <year>2016</year>
          <issue>1-2</issue>
          <fpage>7</fpage>
          <lpage>24</lpage>
          <pub-id pub-id-type="other">VTOVJF</pub-id>
          <pub-id pub-id-type="doi">10.7868/S0205961416010048</pub-id>
        </element-citation>
      </ref>
      <ref id="B20">
        <label>20.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Смолов</surname><given-names>В.Е.</given-names></name>
            <name><surname>Розвадовский</surname><given-names>А.Ф.</given-names></name>
          </person-group>
          <article-title>Применение платформы Arduino для регистрации ветровых волн</article-title>
          <source>Морской гидрофизический журнал</source>
          <year>2020</year>
          <volume>36</volume>
          <issue>4</issue>
          <fpage>467</fpage>
          <lpage>479</lpage>
          <pub-id pub-id-type="other">AKIIBG</pub-id>
          <pub-id pub-id-type="doi">10.22449/0233-7584-2020-4-467-479</pub-id>
        </element-citation>
      </ref>
      <ref id="B21">
        <label>21.</label>
        <element-citation publication-type="book">
          <person-group person-group-type="author">
            <name><surname>Longuet-Higgins</surname><given-names>M.S.</given-names></name>
            <name><surname>Cartwright</surname><given-names>D.E.</given-names></name>
            <name><surname>Smith</surname><given-names>N.D.</given-names></name>
          </person-group>
          <article-title>Observations of the Directional Spectrum of Sea Waves Using the Motions of a Floating Buoy</article-title>
          <source>Ocean wave spectra : Proceedings of a Conference, Easton, Maryland, May 1–4, 1961</source>
          <publisher-loc>Englewood Cliffs</publisher-loc>
          <publisher-name>Prentice-Hall</publisher-name>
          <year>1961</year>
          <fpage>111</fpage>
          <lpage>132</lpage>
        </element-citation>
      </ref>
      <ref id="B22">
        <label>22.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Ashton</surname><given-names>I.G.C.</given-names></name>
            <name><surname>Johanning</surname><given-names>L.</given-names></name>
          </person-group>
          <article-title>On errors in low frequency wave measurements from wave buoys</article-title>
          <source>Ocean Engineering</source>
          <year>2015</year>
          <volume>95</volume>
          <fpage>11</fpage>
          <lpage>22</lpage>
          <pub-id pub-id-type="doi">10.1016/j.oceaneng.2014.11.033</pub-id>
        </element-citation>
      </ref>
      <ref id="B23">
        <label>23.</label>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name><surname>Stewart</surname><given-names>R.H.</given-names></name>
          </person-group>
          <article-title>A discus-hulled wave measuring buoy</article-title>
          <source>Ocean Engineering</source>
          <year>1977</year>
          <volume>4</volume>
          <issue>2</issue>
          <fpage>101</fpage>
          <lpage>107</lpage>
          <pub-id pub-id-type="doi">10.1016/0029-8018(77)90013-0</pub-id>
        </element-citation>
      </ref>
    </ref-list>
  </back>
</article>
