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	<id>http://wiki.icar.org/index.php?action=history&amp;feed=atom&amp;title=Section_20%3A_Laser_Methane_Detector</id>
	<title>Section 20: Laser Methane Detector - Revision history</title>
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	<link rel="alternate" type="text/html" href="http://wiki.icar.org/index.php?title=Section_20:_Laser_Methane_Detector&amp;action=history"/>
	<updated>2026-04-18T20:48:51Z</updated>
	<subtitle>Revision history for this page on the wiki</subtitle>
	<generator>MediaWiki 1.41.1</generator>
	<entry>
		<id>http://wiki.icar.org/index.php?title=Section_20:_Laser_Methane_Detector&amp;diff=4909&amp;oldid=prev</id>
		<title>Cvangemert: Cvangemert moved page Laser Methane Detector to Section 20: Laser Methane Detector</title>
		<link rel="alternate" type="text/html" href="http://wiki.icar.org/index.php?title=Section_20:_Laser_Methane_Detector&amp;diff=4909&amp;oldid=prev"/>
		<updated>2026-02-18T07:40:42Z</updated>

		<summary type="html">&lt;p&gt;Cvangemert moved page &lt;a href=&quot;/index.php/Laser_Methane_Detector&quot; class=&quot;mw-redirect&quot; title=&quot;Laser Methane Detector&quot;&gt;Laser Methane Detector&lt;/a&gt; to &lt;a href=&quot;/index.php/Section_20:_Laser_Methane_Detector&quot; title=&quot;Section 20: Laser Methane Detector&quot;&gt;Section 20: Laser Methane Detector&lt;/a&gt;&lt;/p&gt;
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				&lt;td colspan=&quot;1&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;1&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 07:40, 18 February 2026&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-notice&quot; lang=&quot;en&quot;&gt;&lt;div class=&quot;mw-diff-empty&quot;&gt;(No difference)&lt;/div&gt;
&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;</summary>
		<author><name>Cvangemert</name></author>
	</entry>
	<entry>
		<id>http://wiki.icar.org/index.php?title=Section_20:_Laser_Methane_Detector&amp;diff=4338&amp;oldid=prev</id>
		<title>Bgolden at 10:48, 2 May 2025</title>
		<link rel="alternate" type="text/html" href="http://wiki.icar.org/index.php?title=Section_20:_Laser_Methane_Detector&amp;diff=4338&amp;oldid=prev"/>
		<updated>2025-05-02T10:48:55Z</updated>

		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
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				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 10:48, 2 May 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l1&quot;&gt;Line 1:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 1:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-deleted&quot;&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&amp;lt;center&amp;gt;&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-deleted&quot;&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&amp;lt;big&amp;gt;&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-deleted&quot;&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&amp;lt;b&amp;gt;NOTE: This version of Section 20 has been approved by the working group&#039;s Chair.  Please be aware that further revisions may occur before final review and approval by the Board and ICAR members per the [[Approval of Page Process]].&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-deleted&quot;&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&amp;lt;/b&amp;gt;&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-deleted&quot;&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&amp;lt;/big&amp;gt;&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-deleted&quot;&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&amp;lt;/center&amp;gt;&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-deleted&quot;&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The laser CH&amp;lt;sub&amp;gt;4&amp;lt;/sub&amp;gt; detector (LMD) is a highly responsive, hand-held device that is pointed at an animal’s nostrils and measures CH&amp;lt;sub&amp;gt;4&amp;lt;/sub&amp;gt; column density along the length of the laser beam (ppm.m). In the first implementation of LMD on a farm, measurements for each cow were taken over periods of 15 to 25 seconds between eructation events and could detect CH&amp;lt;sub&amp;gt;4&amp;lt;/sub&amp;gt; emitted each time the animal breathed out (Chagunda et al., 2009&amp;lt;ref&amp;gt;Chagunda, M.G.G., Ross, D., and Robert,s D J. 2009. On the use of a laser methane detector in dairy cows. Comput. Electron. Agric. 68:157-160.&amp;lt;/ref&amp;gt;, Sorg et al., 2016&amp;lt;ref&amp;gt;Sorg, D., Mühlbach, S., Rosner, F., Kuhla, B., Derno, M., Meese, S., Schwarm, A., Kreuzer, M., and Swalve, H. 2016. The agreement between two next-generation laser methane detectors and respiration chamber facilities in recording methane concentrations in the spent air produced by dairy cows. Comp. Electr. Agric. 143:262-272. &amp;lt;/ref&amp;gt;, Sorg et al., 2017&amp;lt;ref&amp;gt;Sorg, D., Difford, G.F., Mühlbach, S., Kuhla, B., Swalve, H.H., Lassen, J., Strabel, T., and Pszczola, M. 2017. Comparison of a laser methane detector with the GreenFeed and two breath analysers for on-farm measurements of methane emissions from dairy cows. Comp. Elec. Agric. 153:285-294.&amp;lt;/ref&amp;gt;). In a later study with sheep and beef cattle, monitoring periods of 2 to 4 minutes allowed authors to separate breathing cycles from eructation events (Ricci et al., 2014&amp;lt;ref&amp;gt;Ricci, P., Chagunda, M.G.G., Rooke, J., Houdijk, J.G.M., Duthie, C-A., Hyslop, J., Roehe, R., and Waterhouse, A. 2014. Evaluation of the laser methane detector to estimate methane emissions from ewes and steers. J. Anim. Sci. 92:5239-5250.&amp;lt;/ref&amp;gt;). Typically, animals are restrained either manually or in head yokes at a feed fence for the required length of time. The operator has to stand at the same distance (1 to 3 m) from each animal every time and must be careful to keep the laser pointed at the animal’s nostrils throughout the measurement period.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The laser CH&amp;lt;sub&amp;gt;4&amp;lt;/sub&amp;gt; detector (LMD) is a highly responsive, hand-held device that is pointed at an animal’s nostrils and measures CH&amp;lt;sub&amp;gt;4&amp;lt;/sub&amp;gt; column density along the length of the laser beam (ppm.m). In the first implementation of LMD on a farm, measurements for each cow were taken over periods of 15 to 25 seconds between eructation events and could detect CH&amp;lt;sub&amp;gt;4&amp;lt;/sub&amp;gt; emitted each time the animal breathed out (Chagunda et al., 2009&amp;lt;ref&amp;gt;Chagunda, M.G.G., Ross, D., and Robert,s D J. 2009. On the use of a laser methane detector in dairy cows. Comput. Electron. Agric. 68:157-160.&amp;lt;/ref&amp;gt;, Sorg et al., 2016&amp;lt;ref&amp;gt;Sorg, D., Mühlbach, S., Rosner, F., Kuhla, B., Derno, M., Meese, S., Schwarm, A., Kreuzer, M., and Swalve, H. 2016. The agreement between two next-generation laser methane detectors and respiration chamber facilities in recording methane concentrations in the spent air produced by dairy cows. Comp. Electr. Agric. 143:262-272. &amp;lt;/ref&amp;gt;, Sorg et al., 2017&amp;lt;ref&amp;gt;Sorg, D., Difford, G.F., Mühlbach, S., Kuhla, B., Swalve, H.H., Lassen, J., Strabel, T., and Pszczola, M. 2017. Comparison of a laser methane detector with the GreenFeed and two breath analysers for on-farm measurements of methane emissions from dairy cows. Comp. Elec. Agric. 153:285-294.&amp;lt;/ref&amp;gt;). In a later study with sheep and beef cattle, monitoring periods of 2 to 4 minutes allowed authors to separate breathing cycles from eructation events (Ricci et al., 2014&amp;lt;ref&amp;gt;Ricci, P., Chagunda, M.G.G., Rooke, J., Houdijk, J.G.M., Duthie, C-A., Hyslop, J., Roehe, R., and Waterhouse, A. 2014. Evaluation of the laser methane detector to estimate methane emissions from ewes and steers. J. Anim. Sci. 92:5239-5250.&amp;lt;/ref&amp;gt;). Typically, animals are restrained either manually or in head yokes at a feed fence for the required length of time. The operator has to stand at the same distance (1 to 3 m) from each animal every time and must be careful to keep the laser pointed at the animal’s nostrils throughout the measurement period.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Bgolden</name></author>
	</entry>
	<entry>
		<id>http://wiki.icar.org/index.php?title=Section_20:_Laser_Methane_Detector&amp;diff=1257&amp;oldid=prev</id>
		<title>Lbenzoni at 13:50, 6 March 2024</title>
		<link rel="alternate" type="text/html" href="http://wiki.icar.org/index.php?title=Section_20:_Laser_Methane_Detector&amp;diff=1257&amp;oldid=prev"/>
		<updated>2024-03-06T13:50:13Z</updated>

		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
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				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 13:50, 6 March 2024&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l1&quot;&gt;Line 1:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 1:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The laser &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;CH4 &lt;/del&gt;detector (LMD) is a highly responsive, hand-held device that is pointed at an animal’s nostrils and measures &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;CH4 &lt;/del&gt;column density along the length of the laser beam (ppm.m). In the first implementation of LMD on a farm, measurements for each cow were taken over periods of 15 to 25 seconds between eructation events and could detect &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;CH4 &lt;/del&gt;emitted each time the animal breathed out (Chagunda et al., 2009 Sorg et al., 2016, 2017). In a later study with sheep and beef cattle, monitoring periods of 2 to 4 minutes allowed authors to separate breathing cycles from eructation events (Ricci et al., 2014). Typically, animals are restrained either manually or in head yokes at a feed fence for the required length of time. The operator has to stand at the same distance (1 to 3 m) from each animal every time and must be careful to keep the laser pointed at the animal’s nostrils throughout the measurement period.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The laser &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;CH&amp;lt;sub&amp;gt;4&amp;lt;/sub&amp;gt; &lt;/ins&gt;detector (LMD) is a highly responsive, hand-held device that is pointed at an animal’s nostrils and measures &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;CH&amp;lt;sub&amp;gt;4&amp;lt;/sub&amp;gt; &lt;/ins&gt;column density along the length of the laser beam (ppm.m). In the first implementation of LMD on a farm, measurements for each cow were taken over periods of 15 to 25 seconds between eructation events and could detect &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;CH&amp;lt;sub&amp;gt;4&amp;lt;/sub&amp;gt; &lt;/ins&gt;emitted each time the animal breathed out (Chagunda et al., 2009&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&amp;lt;ref&amp;gt;Chagunda, M.G.G., Ross, D., and Robert,s D J. 2009. On the use of a laser methane detector in dairy cows. Comput. Electron. Agric. 68:157-160.&amp;lt;/ref&amp;gt;, &lt;/ins&gt;Sorg et al., 2016&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&amp;lt;ref&amp;gt;Sorg, D., Mühlbach, S., Rosner, F., Kuhla, B., Derno, M., Meese, S., Schwarm, A., Kreuzer, M., and Swalve, H. 2016. The agreement between two next-generation laser methane detectors and respiration chamber facilities in recording methane concentrations in the spent air produced by dairy cows. Comp. Electr. Agric. 143:262-272. &amp;lt;/ref&amp;gt;, Sorg et al., 2017&amp;lt;ref&amp;gt;Sorg, D., Difford, G.F., Mühlbach, S., Kuhla, B., Swalve, H.H., Lassen, J., Strabel, T.&lt;/ins&gt;, &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;and Pszczola, M. &lt;/ins&gt;2017&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;. Comparison of a laser methane detector with the GreenFeed and two breath analysers for on-farm measurements of methane emissions from dairy cows. Comp. Elec. Agric. 153:285-294.&amp;lt;/ref&amp;gt;&lt;/ins&gt;). In a later study with sheep and beef cattle, monitoring periods of 2 to 4 minutes allowed authors to separate breathing cycles from eructation events (Ricci et al., 2014&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&amp;lt;ref&amp;gt;Ricci, P., Chagunda, M.G.G., Rooke, J., Houdijk, J.G.M., Duthie, C-A., Hyslop, J., Roehe, R., and Waterhouse, A. 2014. Evaluation of the laser methane detector to estimate methane emissions from ewes and steers. J. Anim. Sci. 92:5239-5250.&amp;lt;/ref&amp;gt;&lt;/ins&gt;). Typically, animals are restrained either manually or in head yokes at a feed fence for the required length of time. The operator has to stand at the same distance (1 to 3 m) from each animal every time and must be careful to keep the laser pointed at the animal’s nostrils throughout the measurement period.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Lbenzoni</name></author>
	</entry>
	<entry>
		<id>http://wiki.icar.org/index.php?title=Section_20:_Laser_Methane_Detector&amp;diff=1072&amp;oldid=prev</id>
		<title>Lbenzoni: Created page with &quot;The laser CH4 detector (LMD) is a highly responsive, hand-held device that is pointed at an animal’s nostrils and measures CH4 column density along the length of the laser beam (ppm.m). In the first implementation of LMD on a farm, measurements for each cow were taken over periods of 15 to 25 seconds between eructation events and could detect CH4 emitted each time the animal breathed out (Chagunda et al., 2009 Sorg et al., 2016, 2017). In a later study with sheep and b...&quot;</title>
		<link rel="alternate" type="text/html" href="http://wiki.icar.org/index.php?title=Section_20:_Laser_Methane_Detector&amp;diff=1072&amp;oldid=prev"/>
		<updated>2024-02-14T20:14:10Z</updated>

		<summary type="html">&lt;p&gt;Created page with &amp;quot;The laser CH4 detector (LMD) is a highly responsive, hand-held device that is pointed at an animal’s nostrils and measures CH4 column density along the length of the laser beam (ppm.m). In the first implementation of LMD on a farm, measurements for each cow were taken over periods of 15 to 25 seconds between eructation events and could detect CH4 emitted each time the animal breathed out (Chagunda et al., 2009 Sorg et al., 2016, 2017). In a later study with sheep and b...&amp;quot;&lt;/p&gt;
&lt;p&gt;&lt;b&gt;New page&lt;/b&gt;&lt;/p&gt;&lt;div&gt;The laser CH4 detector (LMD) is a highly responsive, hand-held device that is pointed at an animal’s nostrils and measures CH4 column density along the length of the laser beam (ppm.m). In the first implementation of LMD on a farm, measurements for each cow were taken over periods of 15 to 25 seconds between eructation events and could detect CH4 emitted each time the animal breathed out (Chagunda et al., 2009 Sorg et al., 2016, 2017). In a later study with sheep and beef cattle, monitoring periods of 2 to 4 minutes allowed authors to separate breathing cycles from eructation events (Ricci et al., 2014). Typically, animals are restrained either manually or in head yokes at a feed fence for the required length of time. The operator has to stand at the same distance (1 to 3 m) from each animal every time and must be careful to keep the laser pointed at the animal’s nostrils throughout the measurement period.&lt;/div&gt;</summary>
		<author><name>Lbenzoni</name></author>
	</entry>
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