edited by Susan M. Hincliff
Churchill livingstone , 1979
Buku Teks SO
Tornyay, Rheba de
John Wiley & Sons, 1987
Buku Teks SO
Billings, Diane M.
W.B. Saunders, 1998
Buku Teks SO
Helen L. Van Hoozer [and others]
Appleton Century Crofts, 1987
Buku Teks SO
Reilly, Dorothy E.
Jones and Bartlett, 1999
Buku Teks SO