Villegas, B. M. (1989). Improving the lines of 18m Filipinos. IN The Positive sum game [column]. Manila Chronicle.
Chicago-viite (17. p.)Villegas, Bernardo M. "Improving the Lines of 18m Filipinos. IN The Positive Sum Game [column]." Manila Chronicle 1989.
MLA-viite (9. p.)Villegas, Bernardo M. "Improving the Lines of 18m Filipinos. IN The Positive Sum Game [column]." Manila Chronicle, 1989.
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