TY - RPRT TI - Long-period events, the most characteristic seismicity accompanying the emplacement and extrusion of a lava dome in Galeras Volcano, Colombia, in 1991 AU - Cruz F. Gil AU - B. A. Chouet PY - 1997 UR - https://pubs.usgs.gov/publication/70019754 ID - 70019754 ER -