Mortimer, Charles E.
Publishing, 1983
Buku Teks
Suckling, Colin J.
Universal Book Stall, 1995
Buku Teks
Latchem, W.E.
Hutchinson Educational , 1972
Buku Teks
Sienko, Michell J., author
McGraw-Hill Kogakusha, 1961
Buku Teks
Busch, Daryle H., author
Allyn and Bacon , 1978
Buku Teks