Paper  bibtex   

@collection{biserkovRedDataBook2011,
  title = {Red Data Book of the {{Republic}} of {{Bulgaria}} - {{Volume}} 3: Natural Habitats},
  editor = {Biserkov, Valko and Gussev, Chavdar and Popov, Vassil and Hibaum, Georgi and Roussakova, Veska and Pandurski, Ivan and Uzunov, Yordan and Dimitrov, Marius and Tzonev, Rossen and Tsoneva, Sonya},
  date = {2011},
  publisher = {{Institute of Biodiversity and Ecosystem Research \& Bulgarian Ministry of Environment and Water}},
  location = {{Sofia, Bulgaria}},
  url = {http://e-ecodb.bas.bg/rdb/en/vol3/},
  keywords = {*imported-from-citeulike-INRMM,~INRMM-MiD:c-14015074,bulgaria,habitat-availability,habitat-description,species-distribution}
}