Sotelo, YolandaCardinoza, GabrielArzadon, CristinaBalbin, Leoncio Jr.2020-02-172025-05-232020-02-172013-02-28Sotelo, Y., Cardinoza, G., Arzadon, C., & Balbin, L. Jr. (2013, March 1). Oil sludge removal starts in Ilocos. Philippine Daily Inquirer, p. A20.http://hdl.handle.net/20.500.12174/7842ennewspaperArticlesludgeoil spillsmerchant shipswrecks