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			<nameOfIssuer>Anadarko Petroleum</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>032511107</cusip>
			<value>118818</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1401814</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
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			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>1451814</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>BOK Financial</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>05561Q201</cusip>
			<value>329750</value>
			<shrsOrPrnAmt>
				<sshPrnamt>4775536</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>4775536</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>Petroleo Brasileiros</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>71654V408</cusip>
			<value>28916</value>
			<shrsOrPrnAmt>
				<sshPrnamt>2199000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>2199000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>Unit Corporation</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>909218109</cusip>
			<value>87577</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1339515</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>1339515</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>Direct TV (DTV)</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>25490A309</cusip>
			<value>1621</value>
			<shrsOrPrnAmt>
				<sshPrnamt>21211</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>OTR</investmentDiscretion>
			<votingAuthority>
				<Sole>0</Sole>
				<Shared>0</Shared>
				<None>21211</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>Express Scripts</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>30219G108</cusip>
			<value>1812</value>
			<shrsOrPrnAmt>
				<sshPrnamt>24137</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>OTR</investmentDiscretion>
			<votingAuthority>
				<Sole>0</Sole>
				<Shared>0</Shared>
				<None>24137</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>Gaming &amp; Leisure Properties</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>36467J108</cusip>
			<value>1213</value>
			<shrsOrPrnAmt>
				<sshPrnamt>33271</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>OTR</investmentDiscretion>
			<votingAuthority>
				<Sole>0</Sole>
				<Shared>0</Shared>
				<None>33271</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>Liberty Global - Series C</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>G5480U120</cusip>
			<value>1036</value>
			<shrsOrPrnAmt>
				<sshPrnamt>25453</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>OTR</investmentDiscretion>
			<votingAuthority>
				<Sole>0</Sole>
				<Shared>0</Shared>
				<None>25453</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>Lorillard Inc</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>544147101</cusip>
			<value>923</value>
			<shrsOrPrnAmt>
				<sshPrnamt>17074</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>OTR</investmentDiscretion>
			<votingAuthority>
				<Sole>0</Sole>
				<Shared>0</Shared>
				<None>17074</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>Mastercard CL A</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>57636Q104</cusip>
			<value>666</value>
			<shrsOrPrnAmt>
				<sshPrnamt>8921</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>OTR</investmentDiscretion>
			<votingAuthority>
				<Sole>0</Sole>
				<Shared>0</Shared>
				<None>8921</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>Microsoft Cors (MSFT)</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>594918104</cusip>
			<value>1974</value>
			<shrsOrPrnAmt>
				<sshPrnamt>48155</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>OTR</investmentDiscretion>
			<votingAuthority>
				<Sole>0</Sole>
				<Shared>0</Shared>
				<None>48155</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>Penn National Gaming</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>707569109</cusip>
			<value>547</value>
			<shrsOrPrnAmt>
				<sshPrnamt>44381</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>OTR</investmentDiscretion>
			<votingAuthority>
				<Sole>0</Sole>
				<Shared>0</Shared>
				<None>44381</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>Philip Morris</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>718172109</cusip>
			<value>1217</value>
			<shrsOrPrnAmt>
				<sshPrnamt>14863</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>OTR</investmentDiscretion>
			<votingAuthority>
				<Sole>0</Sole>
				<Shared>0</Shared>
				<None>14863</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>Republic Services</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>760759100</cusip>
			<value>1443</value>
			<shrsOrPrnAmt>
				<sshPrnamt>42241</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>OTR</investmentDiscretion>
			<votingAuthority>
				<Sole>0</Sole>
				<Shared>0</Shared>
				<None>42241</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>Starz Liberty</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>85571Q102</cusip>
			<value>962</value>
			<shrsOrPrnAmt>
				<sshPrnamt>29808</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>OTR</investmentDiscretion>
			<votingAuthority>
				<Sole>0</Sole>
				<Shared>0</Shared>
				<None>29808</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>Taminco</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>87509U106</cusip>
			<value>702</value>
			<shrsOrPrnAmt>
				<sshPrnamt>33403</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>OTR</investmentDiscretion>
			<votingAuthority>
				<Sole>0</Sole>
				<Shared>0</Shared>
				<None>33403</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>Valeant Pharmaceuticals</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>91911K102</cusip>
			<value>1505</value>
			<shrsOrPrnAmt>
				<sshPrnamt>11418</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>OTR</investmentDiscretion>
			<votingAuthority>
				<Sole>0</Sole>
				<Shared>0</Shared>
				<None>11418</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>Viacom</nameOfIssuer>
			<titleOfClass>Common</titleOfClass>
			<cusip>92553P201</cusip>
			<value>968</value>
			<shrsOrPrnAmt>
				<sshPrnamt>11395</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>OTR</investmentDiscretion>
			<votingAuthority>
				<Sole>0</Sole>
				<Shared>0</Shared>
				<None>11395</None>
			</votingAuthority>
		</infoTable>
</informationTable>
