Johnson, Glen M.
McGraw-Hill, 1999
Buku Teks
Johnson, Glenn M.
McGraw-Hill, 1999
Buku Referensi
Brandi, Ulrike
Birkhäuser, 2001.
Buku Teks SO
Whitehead, Randall
Rockport Publishers, 1993
Buku Referensi
Niesewand, Nonie
Mitchell Beazley, 1995
Buku Referensi