Keller, S. J., & Abdulkareem, T. F. (1980). Post-Knox unconformity--significance at Unionport gas-storage project and relationship to petroleum exploration in Indiana. State of Indiana, Dept. of Natural Resources, Geological Survey.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Keller, Stanley J., و Talal F. Abdulkareem. Post-Knox Unconformity--significance at Unionport Gas-storage Project and Relationship to Petroleum Exploration in Indiana. Bloomington, Ind.: State of Indiana, Dept. of Natural Resources, Geological Survey, 1980.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Keller, Stanley J., و Talal F. Abdulkareem. Post-Knox Unconformity--significance at Unionport Gas-storage Project and Relationship to Petroleum Exploration in Indiana. State of Indiana, Dept. of Natural Resources, Geological Survey, 1980.