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I. M.  Raichev and Sabeva, S., ?New data for Staphylinidae, Coleoptera from the Rila Mountain ?, "Godishnik na Sofiiskiia Universitet ""Kliment Okhridski"" Biologicheski Fakultet, vol. 78 (1-Zoologiya), pp.  80-84, 1987.

I. M.  Raichev, ?Ecological groups and morphoecological characteristic of the investigated from the family Staphylinidae (Coleoptera) from the region of Pleven district?, Izvestiia na Muzeite v Severozapadna BulgariiaIzvestiia na Muzeite v Severozapadna Bulgariia, vol. 12 , pp. 157-172, 1987.