Abaya, E. F. (1996). Coding telephone number to avoid “wrong numbers”. Philippine Engineering Journal.
Citación estilo ChicagoAbaya, Efren F. "Coding Telephone Number to Avoid “wrong Numbers”." Philippine Engineering Journal 1996.
Cita MLAAbaya, Efren F. "Coding Telephone Number to Avoid “wrong Numbers”." Philippine Engineering Journal, 1996.
Warning: These citations may not always be 100% accurate.