Watson, William
Max Parrish, 1960
Buku Teks
edited by Kathryn A. Bard ; editing assistance of Steven Blake Shubert
Routledge, 1999
Buku Referensi
Bard, Kathryn A.
Blackwell Publishing, 2008
Buku Teks
edited by Jacquetta Hawkes
McGraw-Hill, 1974
Buku Referensi
Schafer, Edward H.
Time-Life International, 1968
Buku Teks