Velasquez, Manuel G., author
Pearson, 2006
Buku Teks
Johnson, Rossall James, 1917-, author
LPEM - FEUI, 1961
Buku Teks
Handler, Milton
University Casebook, 1972
Buku Teks
Wyat, John W.
McGraw-Hill, 1963
Buku Teks
Velasquez, Manuel G
Prentice-Hall, 2002
Buku Teks