Alarilla, J. G. (1999). PLDT opens call management cneter to monitor center to monitor voice traffic. Philippine Daily Inquirer.
Chicago Style aipamenaAlarilla, Joey G. "PLDT Opens Call Management Cneter to Monitor Center to Monitor Voice Traffic." Philippine Daily Inquirer 1999.
MLA aipamenaAlarilla, Joey G. "PLDT Opens Call Management Cneter to Monitor Center to Monitor Voice Traffic." Philippine Daily Inquirer, 1999.
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