Swanson, L. (1949). Topographic Manual. United States Goverment Printing Office.
Cita Chicago Style (17a ed.)Swanson, L.W. Topographic Manual. Washington: United States Goverment Printing Office, 1949.
Cita MLA (9a ed.)Swanson, L.W. Topographic Manual. United States Goverment Printing Office, 1949.
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