by IVANOV,IVAN M.,BG
Year of Publication 15.06.1988

by IVANOV,IVAN M.,BG, B'RZEV,GEORGI I.,BG, KLISURANOV,GEORGI S.,BG
Year of Publication 15.12.1988

by KLISSURANOV,GEORGI S.,BG, IVANOV IVAN M.,BG, ANTONOV,VENZISLAV M.,BG, BARSEV GEORGI I.,BG, DONTSCHEV,RAJTSCHO V.,BG
Year of Publication 13.08.1984