APA (7th ed.) Citation

De Leon, H. S. (1987). Textbook on the new Philippine constitution (1987 ed.). Rex Book Store.

Chicago Style (17th ed.) Citation

De Leon, Hector S. Textbook on the New Philippine Constitution. 1987 ed. Manila: Rex Book Store, 1987.

MLA (9th ed.) Citation

De Leon, Hector S. Textbook on the New Philippine Constitution. 1987 ed. Rex Book Store, 1987.

Warning: These citations may not always be 100% accurate.