Hansen, Alvin H. (Alvin Harvey), 1887-1975, author
W.W. Norton, 1941
Buku Teks
Lundberg, Erik, author
Harvard University Press, 1957
Buku Teks
Hamberg, Daniel, author
Macmillan, 1951
Buku Teks
Hald, Earl C., author
Houghton-Mifflin, 1954
Buku Teks
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