by Norman Lawrence ... [and others]
Oxford University Press, 1997
Buku Referensi
Edworthy, Niall
Transworls Publishers, 2010
Buku Referensi
Seymour I. Schwartz, G. Tom Shires, Frank C. Spencer
McGraw-Hill, 1994
Buku Teks SO
edited by Alfred P. Fishman
McGraw-Hill, 1994
Buku Teks SO
Adel A.F. Mahmoud
McGraw-Hill, 1993
Buku Teks SO