Herrera, A. (1999). Highly active absorbent for SO2 removal prepared from coal ash (Part 3). Philippine Engineering Journal.
Chicago Style aipamenaHerrera, A.B. "Highly Active Absorbent for SO2 Removal Prepared from Coal Ash (Part 3)." Philippine Engineering Journal 1999.
MLA aipamenaHerrera, A.B. "Highly Active Absorbent for SO2 Removal Prepared from Coal Ash (Part 3)." Philippine Engineering Journal, 1999.
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