Ryan, Gig, author
Pan Books, 1990
Buku Teks
Church, Horace K., author
McGraw-Hill, 1981
Buku Referensi
Herrick, James A., author
Pearson custom, 1998
Buku Teks
Cornman, James W., author
Macmillan, 1968
Buku Teks
Mander, Jerry, author
Morrow Quill Paperbacks, 1978
Buku Teks