Schele, Linda, and Miller, Mary. 1986. The Blood Of Kings: Dynasty And Ritual In Maya Art. New York: George Braziller, Inc.: 270, Fig. VII.1;
Freidel, David A., Linda Schele, and Joy Parker. 1993. Maya Cosmos: Three Thousand Years on the Shaman's Path. New York: W. Morrow: 90, Fig. 2: 25; 245, Fig. 5: 6c