[compiled by] Lauri Miller
Ohio North Light Books, 1992
Buku Teks SO
arranged and edited by Wolfgang Hageney
Belvedere, 1989
Buku Teks SO
Harper, Laurel
Chronicle Books, 1999
Buku Referensi
Geary, David M.
Prentice-Hall, 1997
Buku Teks SO
Ramsey
John Wiley & Sons, 1994
Buku Referensi