00552nam a2200145 a 4500 20190520021440.0 080327s19uu xx 00 eng d Philippine Institute of Volcanology and Seismology Operation Mayon : a contingency plan for Mayon Volcano. Quezon City : PHIVOLCS Press, 1990. 38 p. : ill., maps (1 col.) Mayon (Mount) Volcanoes Philippines OLOPSC 35292 35292 0 0 0 0 CLLRC CLLRC FIL 2019-05-20 0 QE 523 M39 P5 1990 CL6816 2021-05-26 00:00:00 2019-05-20 BK