Dyfyniad APA

Birdsall, S. S. (1998). Outline American Geography. USA: United states Infomation Agency.

Dyfyniad Arddull Chicago

Birdsall, Stephen S. Outline American Geography. USA: United states Infomation Agency, 1998.

Dyfyniad MLA

Birdsall, Stephen S. Outline American Geography. USA: United states Infomation Agency, 1998.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.