Deegan, Arthur X., author
Aspen Systems Corp., 1982
Buku Teks
Mac Stravic, Robin E. Scott
Aspen Systems Corp., 1980
Buku Teks
Schulz, Rockwell, author
McGraw-Hill, 1976
Buku Teks
Schulz, Rockwell, author
McGraw-Hill, 1983
Buku Teks
Odiorne, George S., author
Prentice-Hall, 1969
Buku Teks