National Geographic Society (U.S.). Book Division. (1998). Photographs, then and now. National Geographic Society.
Chicagoスタイル(17版)引用形式National Geographic Society (U.S.). Book Division. Photographs, Then and Now. [Washington, D.C.]: National Geographic Society, 1998.
MLA(9版)引用形式National Geographic Society (U.S.). Book Division. Photographs, Then and Now. National Geographic Society, 1998.
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