MPLX mplx lp common units representing limited partner interests NYSE Natural Gas Distribution PAA plains all american pipeline, l.p. - common units representing limited partner interests NYSE Natural Gas Distribution PAGP plains gp holdings, l.p. - class a shares representing limited partner interests NYSE Natural Gas Distribution APA apa corporation NYSE Oil & Gas Production AR antero resources corporation NYSE Oil & Gas Production BRN barnwell industries, inc. AMEX Oil & Gas Production BSM black stone minerals, l.p. common units representing limited partner interests AMEX Oil & Gas Production BTE baytex energy corp common shares NYSE Oil & Gas Production CHKR chesapeake granite watr NYSE Oil & Gas Production CKX ckx lands, inc. AMEX Oil & Gas Production CNQ canadian natural resources limited NYSE Oil & Gas Production CRC california resources corporation AMEX Oil & Gas Production CRK comstock resources, inc. NYSE Oil & Gas Production CRT cross timbers royalty trust NYSE Oil & Gas Production CVE cenovus energy inc NYSE Oil & Gas Production DMLP dorchester minerals, l.p. - common units representing limited partnership interests NASDAQ Oil & Gas Production DVN devon energy corporation NYSE Oil & Gas Production DWSN dawson geophysical company NASDAQ Oil & Gas Production E eni s.p.a. NYSE Oil & Gas Production EC ecopetrol s.a. american depositary shares NYSE Oil & Gas Production EGY vaalco energy, inc. NYSE Oil & Gas Production EOG eog resources, inc. NYSE Oil & Gas Production EPM evolution petroleum corporation, inc. AMEX Oil & Gas Production EQT eqt corporation NYSE Oil & Gas Production FANG diamondback energy, inc. - commmon stock NASDAQ Oil & Gas Production GBR new concept energy, inc AMEX Oil & Gas Production GPOR gulfport energy corporation common shares NASDAQ Oil & Gas Production GPRK geopark ltd common shares NYSE Oil & Gas Production GTE gran tierra energy inc. AMEX Oil & Gas Production HESM hess midstream lp class a share NYSE Oil & Gas Production HP helmerich & payne, inc. NYSE Oil & Gas Production HUSA houston american energy corporation AMEX Oil & Gas Production ISRL israel acquisitions corp - class a ordinary shares NASDAQ Oil & Gas Production KOS kosmos energy ltd. common shares (de) NYSE Oil & Gas Production KRP kimbell royalty partners common units representing limited partner interests NYSE Oil & Gas Production LGCY legacy education inc. NASDAQ Oil & Gas Production MARPS marine petroleum trust - units of beneficial interest NASDAQ Oil & Gas Production MTDR matador resources company NYSE Oil & Gas Production MTR mesa royalty trust NYSE Oil & Gas Production MUR murphy oil corporation NYSE Oil & Gas Production MVO mv oil trust units of beneficial interests NYSE Oil & Gas Production MXC mexco energy corporation AMEX Oil & Gas Production NBR nabors industries ltd. NYSE Oil & Gas Production NE noble corporation plc ordinary shares NYSE Oil & Gas Production NOG northern oil and gas, inc. AMEX Oil & Gas Production NRT north european oil royality trust NYSE Oil & Gas Production OBE obsidian energy ltd. NYSE Oil & Gas Production OXY occidental petroleum corporation NYSE Oil & Gas Production PARR par pacific holdings, inc. AMEX Oil & Gas Production PBA pembina pipeline corp. ordinary shares (canada) NYSE Oil & Gas Production