by BABACHEV, GEORGI N, SECHKOVA, MARIANA P
Year of Publication 15.06.1993

by BABACHEV, GEORGI N, SECHKOVA, MARIANA P
Year of Publication 15.01.1993

by BABACHEV, GEORGI N, VLADIMIROVA, LILIJA P, SECHKOVA, MARIANA P
Year of Publication 15.09.1993

by BABACHEV, GEORGI N, MIKHAJLOVA, JULIJA D, IVANOV, SVETOSLAV A, SECHKOVA, MARIANA P, JOSIFOV, NIKOLAJ A
Year of Publication 30.11.1998

by BABACHEV, GEORGI N, PAUNOV, IVAN M, VLADIMIROVA, LILIJA P, SECHKOVA, MARIANA P
Year of Publication 30.11.1998

by BABACHEV, GEORGI N, GEORGIEV, ATANAS K, SECHKOVA, MARIANA P
Year of Publication 15.11.1990

by BABACHEV, GEORGI N, IVANOV, RADOSLAV T, GEORGIEV, ATANAS K, SECHKOVA, MARIANA P
Year of Publication 16.03.1992

by BABACHEV, GEORGI N, GEORGIEV, ATANAS K, SECHKOVA, MARIANA P, DANGOV, ANGEL V
Year of Publication 16.03.1992

by BABACHEV, GEORGI N, ZEGOV, PETAR D, SECHKOVA, MARIANA P, KOLEV, KIRIL R
Year of Publication 15.07.1991

by BABACHEV, GEORGI N, IVANOV, RADOSLAV T, GEORGIEV, ATANAS K, SECHKOVA, MARIANA P
Year of Publication 15.03.1990

by BABACHEV, GEORGI N, SECHKOVA, MARIANA P, ZAKHARIEVA, IRINA V, KOLEV, KIRIL R
Year of Publication 16.10.1989

by VLADIMIROVA, LILIJA P, SECHKOVA, MARIANA P, PANDURSKI, JORDAN T
Year of Publication 31.10.2001

by BABACHEV, GEORGI N, SIMEONOV, SIMEON V, TUMBANOV, DIMITAR K, SECHKOVA, MARIANA P, KOLEV, KIRIL R, MIRCHEV, IVAN S
Year of Publication 15.08.1991