Universitas Katolik Parahiyangan, {s.a}
Majalah, Jurnal, Buletin
Koko Martono, author
Alvica Gracia, 1987
Buku Teks
Thomas, George B., author
Addison-Wesley, 1961
Buku Teks
Small, Donald B., author
McGraw-Hill, 1990
Buku Teks
Legros, Roger
Prentice-Hall, 1961
Buku Teks