1. Some natures of volcanic micro-tremors at the Sakurajima volcano (in Japanese);Kamo;Bull. Volcanol. Soc. Japan Ser.,1977
2. The relationship between micro-earthquake swarms and volcanic activity at Sakurajima volcano (in Japanese);Ishihara;Ann. Disast. Prev. Res. Inst., Kyoto Univ.,1989
3. Volcanic B-type earthquake swarm preceding volcanic explosions (in Japanese);Nishi;Ann. Disast. Prev. Res. Inst., Kyoto Univ.,1984