Graddy, Duane B., author
Reston , 1985
Buku Teks
Reed, Edward Wilson, 1913-, author
Prentice-Hall, 1989
Buku Teks
Bradford, Frederick A., author
Longmans, Green, 1932
Buku Teks
edited by Deane Carson
Richard D. Irwin, 1963
Buku Teks
Lampert, Hope, author
Atheneum, 1986
Buku Teks