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Svetoslav Spasov
Bulgarian Society for the Protection of Birds / BirdLife Bulgaria, P.O. Box 50, BG–1111 Sofia, Bulgaria
Volen Arkumarev
Bulgarian Society for the Protection of Birds / BirdLife Bulgaria, P.O. Box 50, BG–1111 Sofia, Bulgaria
Dobromir Dobrev
Bulgarian Society for the Protection of Birds / BirdLife Bulgaria, P.O. Box 50, BG–1111 Sofia, Bulgaria
Vladimir Dobrev
Bulgarian Society for the Protection of Birds / BirdLife Bulgaria, P.O. Box 50, BG–1111 Sofia, Bulgaria