Siagian, Sondang P.
[publisher not identified], 1998
Buku Teks
Siagian, Renville
Gadjah Mada University press, 1997
Buku Teks
Tampubolon, Daulat Purnama
Gramedia Pustaka Utama, 2001
Buku Teks
Koontz, Harold
Erlangga, 1989
Buku Teks
Stoner, James A.F. (Arthur Finch)
Intermedia, 1986
Buku Teks