Birdsall, S. S. (1998). Outline American Geography. USA: United states Infomation Agency.
Trích dẫn kiểu ChicagoBirdsall, Stephen S. Outline American Geography. USA: United states Infomation Agency, 1998.
MLA CitationBirdsall, Stephen S. Outline American Geography. USA: United states Infomation Agency, 1998.
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