Dr. Susan Shillinglaw (January 18, 2004). "John Steinbeck, American Writer". The Martha Heasley Cox Center for Steinbeck Studies. Archived from the original on September 8, 2006. Retrieved December 28, 2006.
Dr. Susan Shillinglaw (January 18, 2004). "John Steinbeck, American Writer". The Martha Heasley Cox Center for Steinbeck Studies. Archived from the original on September 8, 2006. Retrieved December 28, 2006.