Luthans, Fred, author
Macmillan, 1976
Buku Teks
Tribe, Laurence H.
Norton, 1992
Buku Teks
Committee for Economic Development , 1972
Buku Teks
Alderfer, E.B., author
McGraw-Hill, 1950
Buku Teks
Djuretna A. Imam Muhni, author
Gadjah Mada University Press , 1994
Buku Teks