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Jossey-Bass, 1973
Buku Teks
edited by H.J. Butcher and Ernest Rudd
McGraw-Hill, 1972
Buku Teks
Ministry of Education, 1994
Buku Teks
M.K. (Muhammad Kamil) Tadjudin, author
UI-Press, 1998
Buku Teks
Quality management unit University of Sumatera Utara, 2010
Buku Teks