Gaya APA

S.BIRDSALL, H, J, ., B. (1971). Geography : Regions and Concepts . United States of America: HARM J .De BLIJ,STEPHEN S.BIRDSALL.

Gaya MLA

S.BIRDSALL, HARM, J, .De, BLIJ,STEPHEN. "Geography : Regions and Concepts". United States of America: HARM J .De BLIJ,STEPHEN S.BIRDSALL, 1971. Text.