Boyd, Martin
Penguin Books, 1987
Buku Teks SO
Aukerman, Robert C.
John Wiley & Sons, 1981
Buku Teks
Wallace, Catherine
Oxford University Press, 1993
Buku Teks SO
Bernice E. Cullinan, Roger C. Farr, W. Dorsey Hammond, Nancy L. Roser, Dorothy S. Strickland
Harcourt Brace Jovanovich, Publishers, 1989
Buku Teks SO
Bernice E. Cullinan, Roger C. Farr, W. Dorsey Hammond, Nancy L. Roser, Dorothy S. Strickland
Harcourt Brace Jovanovich, Publishers, 1989
Buku Teks SO