The Nakum Archaeological Project: Investigations on the Banks of the Holmul River. Jarosław Źrałka and Wiesław Koszkul. Foundation for the Advancement of Mesoamerican Studies Report, FAMSI 2007 Jarosław Źrałka Wiesław Koszkul

https://www.academia.edu/7762342/The_Nakum_Archaeological_Project_Investigations_on_the_Banks_of_the_Holmul_River_Jaros%C5%82aw_%C5%B9ra%C5%82ka_and_Wies%C5%82aw_Koszkul_Foundation_for_the_Advancement_of_Mesoamerican_Studies_Report_FAMSI_2007