Ong, E. D. (2002). RP's language advantage slowly slipping away, notes call center leader. Manila Bulletin.
Chicago-viite (17. p.)Ong, Edison Dy. "RP's Language Advantage Slowly Slipping Away, Notes Call Center Leader." Manila Bulletin 2002.
MLA-viite (9. p.)Ong, Edison Dy. "RP's Language Advantage Slowly Slipping Away, Notes Call Center Leader." Manila Bulletin, 2002.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.