Robert K. Sitler (februar 2006). "The 2012 Phenomenon: New Age Appropriation of an Ancient Mayan Calendar". Novo Religio: the Journal of Alternative and Emergent Religions. Berkeley: University of California Press. 9 (3): 24-38. doi:10.1525/nr.2006.9.3.024. ISSN1092-6690. OCLC357082680.
Robert K. Sitler (februar 2006). "The 2012 Phenomenon: New Age Appropriation of an Ancient Mayan Calendar". Novo Religio: the Journal of Alternative and Emergent Religions. Berkeley: University of California Press. 9 (3): 24-38. doi:10.1525/nr.2006.9.3.024. ISSN1092-6690. OCLC357082680.