Placzek, Kanittanan, James, Wilaiwan (1986). "Historical and contemporary meaning of Thai khwan: The use of lexical meaning change as an indicator of cultural change". Religion, Values, and Development in Southeast Asia. Institute of Southeast Asian Studies. pp. 146–166. ISBN978-9971-988-20-3.{{cite book}}: CS1 maint: multiple names: authors list (link)
