Kaplan, Abraham, author
Chandler, 1964
Buku Teks
Corbetta, Piergiorgio, author
Sage Publications , 2003
Buku Teks
Pittenger, David J., author
McGraw-Hill, 2003
Buku Teks
edited by James A. Ciarlo
Sage, 1981
Buku Teks
Wahlsten, Douglas, author
Elsevier, 2011
Buku Teks