[BirdLife International (2004): Birds in Europe: population estimates, trends and conservation status.]Search in Google Scholar
[BirdLife Conservation Series No. 12. - BirdLife International, Cambridge.]Search in Google Scholar
[Božič, L. & Vrezec, A. (2000): Sove Pohorja. - Acrocephalus 21 (98/99): 47-53.]Search in Google Scholar
[Ciach, M. (2005): Abundance and distribution patterns of owls in Pieniny National Park, Southern Poland. - Acta Zoologica Cracoviensia 48A (1/2): 21-33.10.3409/173491505783995680]Search in Google Scholar
[Dejaifve, P.A., Novoa, C. & Prodon, R. (1990): [Habitat and density of the Tengmalm’s Owl Aegolius funereus in the eastern part of the Pyrenees.] - Alauda 58: 267-273. (in French) Domaszewicz, A. (1993): [Owls of Bialowieza Forest.] - Bialymstok, Bialowieza. (In Polish) Gaston, K.J., Blackburn, T.M. & Gregory, R.D. (1999): Does variation in census area confound density comparisons? - Journal of Applied Ecology 36 (2): 191-204.]Search in Google Scholar
[Hakkarainen, H. & Korpimaki, E. (1996): Competitive and predatory interactions among raptors: an observational and experimental study. - Ecology 77 (4): 1134-1142.10.2307/2265582]Search in Google Scholar
[Hakkarainen, H., Korpimaki, E., Koivunen, V. & Ydenberg, R. (2002): Survival of male Tengmalm’s Owls under temporally varying food conditions. - Oecologia 131: 83-88.10.1007/s00442-001-0865-528547515]Search in Google Scholar
[Hayward, G.D., Hayward, P.H. & Garton, E.O. (1993): Ecology of Boreal Owls in the Northern Rocky Mountains, USA. - Wildlife Monographs 124: 1-59.]Search in Google Scholar
[Khokhlova, T.Y., Yakovleva, M.V., Zimin, V.B., Artemyev, A.V., Lapsin, N.V. & Sukhov, A.V. (2005): [Materials on owls of Republic Karelia.] pp. 51-63 In: Volkov, V.S., Morozov, V.V. & Sharikov, V.A. (eds.): Owls of the Northern Eurasia. - Moskva. (in Russian) Kloubec, B. (2003): Breeding of Tengmalm’s Owls (Aegoliusfunereus) in nest-boxes in Šumava Mts.: a summary from the years 1978-2002. - Buteo 13: 75-86.]Search in Google Scholar
[Konig, C., Weich, F. & Becking, J.-H. (1999): Owls. A guide to the Owls of the World. - Pica press, Sussex.]Search in Google Scholar
[Korpimaki, E. (1997): Tengmalm’s Owl Aegolius funereus. pp. 420-421 In: Hagemeijer W.J.M. & Blair M.J. (eds): The EBCC Atlas of European Breeding Birds: Their Distribution and Abundance . - T & A D Poyser, London.]Search in Google Scholar
[Lakušić, D. & Elleboode, C. (2011): Map of habitats of Serbia. - Republic Geodetic Institute, Belgrade.]Search in Google Scholar
[Locker, S. & Flugge, D. (1998): HOhe Siedlungsdichte des Rauhfuskauzes Aegolius funereus in den Hanstedter Bergen, Naturschutzgebiet “Luneburger Heide”. - Vogelwelt 119: 329-336.]Search in Google Scholar
[Matvejev, S.D. (1950): [Distribution and life of birds in Serbia.] - Serbian Academy of Science, Belgrade. (in Serbian) Mammen, U. & Stubbe, M. (2005): Zur Lage der Greifvogel und Eulen in Deutschland 1999-2002. - Vogelwelt 126: 53-65.]Search in Google Scholar
[Matvejev, S.D. & Aleksandrov, R.N. (2002): [Life of the birds of the Kopaonik fifty years ago 1938-1967.] - Serbian Society for History of Science, Belgrade. (in Serbian) ]Search in Google Scholar
[Mikkola, H. (1983): Owls of Europe. - T & A D Poyser, Carlton. Nankinov, D. (2002): [Present situation of population of owls in Bulgaria.] - Berkut 11 (1): 48-60. (in Russian) Pačenovsky, S. & Shurulinkov, P. (2008): Latest data on distribution of the Pygmy Owl (Glaucidium passerinum) in Bulgaria and Slovakia including population density comparison. - Slovak Raptor Journal 2: 91-106.]Search in Google Scholar
[Puzović, S., Simić, D., Saveljić, D., Gergelj, J., Tucakov, M., Stojnić, N., Hulo, I., Ham, I., Vizi, O., Šćiban, M., Ružić, M., Vučanović, M. & Jovanović, T. (2003): [Birds of Serbia and Montenegro - breeding population estimates and trends: 1990-2002.] - Ciconia 12: 35-120. (in Serbian)]Search in Google Scholar
[Puzović, S., Sekulić, G., Stojnić, N., Grubač, B. & Tucakov, M. (2009): [Important Bird Areas in Serbia.] - Ministry of Environment and Spatial Planning, Institute for Nature Conservation of Serbia & Provincial Secretariat of Environmental Protection and Sustainable Development, Belgrade. (in Serbian) ]Search in Google Scholar
[Rajković, D., Puzović, S., Raković, M., Grubač, B., Simović, A., Vučanović, M. & Đorđević, I. (2010): [Records of Boreal Owl in Serbia.] - Ciconia 19: 131-140. (in Serbian) ]Search in Google Scholar
[Rykova, S.Y., Rykov, A.M. & Sivkov, A.V. (2005): [Numbers and distribution owls in Pinega Nature Reserve, Archangelsk Region.] pp. 64-67 In: Volkov, V.S., Morozov, V.V. & Sharikov, V.A. (eds.): Owls of the Northern Eurasia. - Moskva. (in Russian) ]Search in Google Scholar
[Shamovich, D.I. & Shamovich, I.Y. (2005): [Spatial and temporal differences in the association of forest owls in conditions of different landscape types in northern Belarus.] pp. 121-135 In: Volkov, V.S., Morozov, V.V. & Sharikov, V.A. (eds.): Owls of the Northern Eurasia. - Moskva. (in Russian) Shurulinkov, P. & Stoyanov, G. (2006): Some new findings of Pigmy Owl Glaucidium passerinum and Tengmalm’s Owl Aegolius funereus in western and southern Bulgaria. - Acrocephalus 27 (128/129): 65-68.]Search in Google Scholar
[Shurulinkov, P., Stoyanov, G., Tzvetkov, P., Vulchev, K., Kolchagov, R. & Ilieva, M. (2003): Distribution and abundance of Tengmalm’s Owl Aegolius funereus on Mount Pirin, south-west Bulgaria. - Sandgrouse 25 (2): 103-109.]Search in Google Scholar
[Shurulinkov, P., Stoyanov, G., Komitov, E., Daskalova, G. & Ralev, A. (2012): Contribution to the Knowledge on Distribution, Number and Habitat Preferences of Rare and Endangered Birds in Western Rhodopes Mts, Southern Bulgaria. Strigiformes and Piciformes. - Acta Zoologica Bulgarica 64 (1): 43-56.]Search in Google Scholar
[Simeonov, S., Michev, T. & Nankinov, D. (1990): The fauna of Bulgaria. Vol. 20. Aves. Part I. - BAS, Sofia. (in Bulgarian) ]Search in Google Scholar
[Takats, D.L., Francis, M.C., Holroyd, L.G., Duncan, R.J., Mazur, K.M., Cannings, J.R., Harris, W. & Holt, D. (2001): Guidelines for Nocturnal Owl Monitoring in North America. - Beaver Hill Bird Observatory & Bird Studies Canada, Edmonton. ]Search in Google Scholar
[Vacik, R. (1991a): [Some information on the distribution and reproductive biology of the Tengmalm’s Owl, Aegolius funereus in Bohemia and Moravia.] pp. 287-297 In: Juillard, M. (ed.): Rapaces Nocturnes. Actes du 30e Colloque interregional d’ornithologie, Porrentruy (Suisse), 2, 3 et 4 novembre 1990. Prangins, Switzerland. - Societe romande pour l’etude et la protection des oiseaux. (in French) ]Search in Google Scholar
[Vasović, M. (1988): Kopaonik - Geografska monografija. - Stručna knjiga, Beograd.]Search in Google Scholar
[Vrezec, A. (2003): Breeding density and altitudinal distribution of the Ural, Tawny and Boreal Owls in North Dinaric Alps (central Slovenia). - Journal of Raptor Research 37 (1): 55-62.]Search in Google Scholar
[Vrezec, A. & Tome, D. (2004): Habitat selection and patterns of distribution in a hierarchic forest owl guild. - Ornis Fennica 81 (3): 109-118. ]Search in Google Scholar