Cita APA (7th ed.)

Gregorio, E. G. (1980). A practical guide to irrigation canal design. Philippine Engineering Journal.

Cita Chicago (17th ed.)

Gregorio, Enrico G. "A Practical Guide to Irrigation Canal Design." Philippine Engineering Journal 1980.

Cita MLA (9th ed.)

Gregorio, Enrico G. "A Practical Guide to Irrigation Canal Design." Philippine Engineering Journal, 1980.