Philippines. Bureau of Internal Revenue. (1990). Complete 1989 numbered B.I.R. rulings. The Center.
Chicago Style (17th ed.) CitationPhilippines. Bureau of Internal Revenue. Complete 1989 Numbered B.I.R. Rulings. Quezon City: The Center, 1990.
MLA (9th ed.) CitationPhilippines. Bureau of Internal Revenue. Complete 1989 Numbered B.I.R. Rulings. The Center, 1990.
Warning: These citations may not always be 100% accurate.