Cytowanie według stylu APA (wyd. 7)

Simpson, A. (1954). The Nigerian coalfield: The geology of parts of Onitsha, Owerri, and Benue Provinces. By authority of the Nigerian Govt..

Cytowanie według stylu Chicago (wyd. 17)

Simpson, A. The Nigerian Coalfield: The Geology of Parts of Onitsha, Owerri, and Benue Provinces. [Zaria]: By authority of the Nigerian Govt., 1954.

Cytowanie według stylu MLA (wyd. 8)

Simpson, A. The Nigerian Coalfield: The Geology of Parts of Onitsha, Owerri, and Benue Provinces. By authority of the Nigerian Govt., 1954.