Agustin, C. L. (2001). A national ID number system. IN Opinion [column]. Philippine Star.
Lua i Stíl Chicago (17ú heag.)Agustin, Carlos L. "A National ID Number System. IN Opinion [column]." Philippine Star 2001.
Lua MLA (9ú heag.)Agustin, Carlos L. "A National ID Number System. IN Opinion [column]." Philippine Star, 2001.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.