(1998). BIR Tax calendar: BIR enters the age of information technology. Bureau of Internal Revenue.
Lua i Stíl Chicago (17ú heag.)BIR Tax Calendar: BIR Enters the Age of Information Technology. s.l: Bureau of Internal Revenue, 1998.
Lua MLA (9ú heag.)BIR Tax Calendar: BIR Enters the Age of Information Technology. Bureau of Internal Revenue, 1998.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.