Sorel, Nancy Caldwell
New York Arcade 1999,
Buku Teks
Medina, John Fitzgerald
Bahai, 2006
Buku Teks
Holdsworth, Ruth, author
Macmillan, 1982
Buku Teks
Tagliaferri, Louise E.
John Wiley & Sons, 1979
Buku Teks
Crawford, Mary (Mary E.), author
McGraw-Hill, 2000
Buku Teks