Gaya APA

Birdsall, S, S. (1992). Geografi Amerika : garis besar : Regional landscapes of the cenited states of amerika and canada . NY: John Wiley & Sons Ine.

Gaya MLA

Birdsall, Stephen, S. "Geografi Amerika : garis besar : Regional landscapes of the cenited states of amerika and canada". NY: John Wiley & Sons Ine, 1992. Text.