APA (7th ed.) Citation

Gregorio, E. G. Siltation problems in the Calaca Harbor. Philippine Engineering Journal.

Chicago Style (17th ed.) Citation

Gregorio, Enrico G. "Siltation Problems in the Calaca Harbor." Philippine Engineering Journal .

MLA (9th ed.) Citation

Gregorio, Enrico G. "Siltation Problems in the Calaca Harbor." Philippine Engineering Journal, .

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