edited by Carl Eicher and Lawrence Witt
McGraw-Hill , 1964
Buku Teks
edited by Clifton R. Wharton
Aldine Publishig, 1969
Buku Teks
Schultz, Theodore W.
McGraw-Hill, 1953
Buku Teks
Mosher, Arthur T.
Agricultural Development Council , 1969
Buku Teks
Ohkawa, Kazushi
Kinokuniya Bookstore, 1972
Buku Teks