Kuratko, Donald F.
Harcourt College Publishers, 2001
Buku Teks
Steinhoff, Dan
McGraw-Hill, 1979
Buku Teks
by Howard H. Stevenson ... [et al.]
Irwin McGraw-Hill, 2000
Buku Teks
edited by Gary Hoover, Alta Campbell, Patrick Spain
The Reference Press, 1991
Buku Referensi
Cunningham, William H.
South-Western, 1984
Buku Teks