PERMIAN BASIN AREA RATE CASES. The Oyez Project at IIT Chicago-Kent College of Law. 12 February 2012. <http://www.oyez.org/cases/1960-1969/1967/1967_90>.
PERMIAN BASIN AREA RATE CASES, The Oyez Project at IIT Chicago-Kent College of Law, http://www.oyez.org/cases/1960-1969/1967/1967_90 (last visited February 12, 2012).
"PERMIAN BASIN AREA RATE CASES," The Oyez Project at IIT Chicago-Kent College of Law, accessed February 12, 2012, http://www.oyez.org/cases/1960-1969/1967/1967_90.