Human activities can hinder the breeding of a top avian predator: preliminary results
Dobrev, Dobromir, Dobrev, Vladimir, Demerdzhiev, Dimitar
The Goosander Mergus merganser range expansion on the Balkan Peninsula and a new breeding population in Bulgaria
Dobrev, Dobromir, Borisov, Borislav, Dobrev, Vladimir, Arkumarev, Volen, Angelov, Ivaylo, Stoychev, Stoycho
An overview of monitoring for raptors in Bulgaria
Spasov, Svetoslav, Arkumarev, Volen, Dobrev, Dobromir, Dobrev, Vladimir