Bayos, K. (2015). PNR is not ready to adopt automated fare collection system. Manila Bulletin.
Chicago Style aipamenaBayos, Kris. "PNR Is Not Ready to Adopt Automated Fare Collection System." Manila Bulletin 2015.
MLA aipamenaBayos, Kris. "PNR Is Not Ready to Adopt Automated Fare Collection System." Manila Bulletin, 2015.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.