Borlagdan, P. C. Design and development of a two post rotary-percussion drilling rig. Philippine Engineering Journal.
Chicago Style (17th ed.) CitationBorlagdan, Paterno C. "Design and Development of a Two Post Rotary-percussion Drilling Rig." Philippine Engineering Journal .
MLA (9th ed.) CitationBorlagdan, Paterno C. "Design and Development of a Two Post Rotary-percussion Drilling Rig." Philippine Engineering Journal, .
Warning: These citations may not always be 100% accurate.