Stevenson, Gladys T., author
John Wiley & Sons, 1960
Buku Teks
Dudek, Susan G., author
J.B. Lippincott, 1997
Buku Teks
Beal, Virginia A.
Macmillan, 1986
Buku Teks
Alford, Betty B.
Prentice-Hall, 1982
Buku Teks
Green, Marilyn L., author
John Wiley & Sons, 1981
Buku Teks