Arthur, Lowel Jay, author
Wiley, 1991
Buku Teks
McKeehan, Julie, author
AP Professional, 1994
Buku Teks
McKeehan, Julie, author
AP Professional, 1994
Buku Teks
Rodgers, Beth L., author
Saunders , 1993
Buku Teks
Rodgers, Beth L., author
Saunders , 2000
Buku Teks