APA (7th ed.) Citation

De Leon, H. S., & De Leon, H. M. (2011). Textbook on the Philippine constitution (2011 ed.). Rex Book Store.

Chicago Style (17th ed.) Citation

De Leon, Hector S., and Hector M. De Leon. Textbook on the Philippine Constitution. 2011 ed. Manila: Rex Book Store, 2011.

MLA (9th ed.) Citation

De Leon, Hector S., and Hector M. De Leon. Textbook on the Philippine Constitution. 2011 ed. Rex Book Store, 2011.