Affiliation: | Geophysical Institute of the Ukrainian Academy of Science, Seismological Dept., Studencheskaya str. 3, 333001 Simferopol, USSR;Geophysical Institute of the Bulgarian Academy of Science, Seismological Dept., G. Boncheu str., bl. 3, 1113 Sofia, Bulgaria;Geological Institure of the Bulgarian Academy of Science, Hydrogeological Dept., G. Bonchev str., bl. 24, 1113 Sofia, Bulgaria |