Geddes-Brown, Leslie, author
Page One, 2000
Buku Referensi
A Ward Lock Book, 1997
Buku Referensi
Rocknow, H.K., author
Stuttman, 1954
Buku Teks
Dooley, Susan, author
Chronicle Books, 2001
Buku Referensi
Bliss, Sara, author
Page One Publishing, 2003
Buku Referensi