Schele, Linda, and Peter Mathews. 1998. The Code of Kings: The Language of Seven Sacred Maya Temples and Tombs. New York: Scribner: 8: 144, Fig. 4.13D
Freidel, L. Schele, and J. Parker, Maya Cosmos: Three Thousand Years on the Shaman's Path, 1993: 215, Fig. 4.27c; 282, Fig. 6.20b