edited by Albert Parker
McGraw-Hill, 1978
Buku Referensi
Paul L. Magill, Francis R. Holden, Charles Ackley, editor; Frederick G. Sawyer, editorial consultant
McGraw-Hill, 1956
Buku Referensi
Davenport, S.J.
Washington, DC: United States Department of the Interior, 1954
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Freeman, Harry M.
McGraw-Hill, 1971
Buku Referensi
Freeman, Harry M.
McGraw-Hill, [1995;1995, 1995]
Buku Referensi