APA

Ruark J., Sohns H., United States of America. Department of the Interior & Sohns H. (1971). Gas combustion retorting of oil shale under anvil points lease agreement: Stage II. United States of America: Bureau of Mines.

Chicago

Ruark J.R, Sohns H.W, United States of America. Department of the Interior and Sohns H.W. 1971. Gas combustion retorting of oil shale under anvil points lease agreement: Stage II. United States of America: Bureau of Mines.

Harvard

Ruark J., Sohns H., United States of America. Department of the Interior and Sohns H. (1971). Gas combustion retorting of oil shale under anvil points lease agreement: Stage II. United States of America: Bureau of Mines.

MLA

Ruark J.R, Sohns H.W, United States of America. Department of the Interior and Sohns H.W. Gas combustion retorting of oil shale under anvil points lease agreement: Stage II. United States of America: Bureau of Mines. 1971.