<informationTable xmlns="http://www.sec.gov/edgar/document/thirteenf/informationtable">		<infoTable>
			<nameOfIssuer>Extraction Oil and Gas Inc</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>30227M105</cusip>
			<value>16325</value>
			<shrsOrPrnAmt>
				<sshPrnamt>7700358</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1, 2</otherManager>
			<votingAuthority>
				<Sole>7700358</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>Ramaco Res Inc</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>75134P303</cusip>
			<value>41068</value>
			<shrsOrPrnAmt>
				<sshPrnamt>11471525</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>DFND</investmentDiscretion>
			<otherManager>1, 2</otherManager>
			<votingAuthority>
				<Sole>11471525</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
</informationTable>
