The Owls of Bulgaria, ISBN 954-500-103-8
Waterbirds of Bourgas Wetlands, ISBN 954-9959-33-3
Atlas of the Breeding Birds in Bulgaria, BSPB, Conservation series, Book 10, ISBN 978-954-91421-7-4
Guide for the nature, ISBN 978-954-91790-3-3
Guide of animals and flowers included in Washington Convention — CITIES, ISBN 954-90820-8-3
Mammals of Rhodopi Mountains, ISBN 954-90601-3-6
Trees and Shrubs of National Park ‘Vitosha Mountain’
Drogflowers in Bulgaria, ISBN 954-642-117-0
Advances in Heteroptera Research, ISBN 978-954-642-311-5 (HB)
Red Data Book (insects, invertebrates, birds), in print
Ignatov, A., 2024. Long-term trend and population density of the Little Owl (Athene noctua) in Bulgaria. — North-Western Journal of Zoology, 20 (1): 65—72.
Spassov, N., Ignatov, A., Mihaylov, Ts., 2023. New evidence for the recent presence of the lynx, Lynx lynx (Linnaeus), in Western Stara Planina Mountains, Bulgaria. — Historia naturalis bulgarica, 45: 53—56.
Ignatov, A., 2023. Modelling the Distribution of the Little Owl Athene noctua in Bulgaria. — C. R. Acad. Bulg. Sci., 76 (12): 1835—1842.
Spassov, N., Askerov, E., Ignatov, A., Acosta-Pankov, I., 2021. New data on the status of the jungle cat (Felis chaus Schreber, 1777) in Azerbaijan. — Historia naturalis bulgarica, 42: 1—3. doi:10.48027/hnb.42.011
Ignatov, A., Popgeorgiev, G., 2021. Recent and Historical Distribution of Little Owl (Athene noctua) in Bulgaria. — AIRO, 29: 216—222.
Spassov, N., Askerov, E., Akosta-Pankov, I., Ignatov, A., 2019. New data on the occurrence of Panthera pardus in the Talysh Mountains, Azerbaijan (Carnivora: Felidae). — Lynx, 50: 113—118.
Michev, T., Profirov, L., Michev, B., Hristov, L., Ignatov, A., Stoynov, E., Chipev, N., 2018. Long-term Changes in Autumn Migration of Selected Soaring Bird Species at Burgas Bay, Bulgaria. — Acta zool. Bulg., 70 (1): 57—68.
Spassov, N., Ignatov, A., Acosta-Pankov, I., 2016. On the status of the leopard in Turkey, again. — CAT news, 64: 18—21.
Spassov, N., Ignatov, A., Acosta-Pankov, I., 2015. The Story of the Turkish Dhole. Exploring and documenting diversity in nature. — CETAF Newsletter, October 2015.
Ignatov, A., Mitev, D., Berkelder, R., van der Poel, P., 2015. Isabelline Shrike Lanius isabellinus: a new species to the Bulgarian avifauna. — Acrocephalus, 36 (164/165): 79—82.