Shurulinkov, P., Hubenov, Z., Beshkov, S., Popgeorgiev, G. (eds), 2019. Biodiversity of the Bulgarian-Romanian section of the Lower Danube. — Nova Publishers, New York, 441 pp.
Popgeorgiev, G., Naumov, B., Kornilev, Y., Vergilov, V., Slavchev, M., Lukanov, S., Dyugmegdzhiev, A., Stoyanov, A., Dobrev, D., Tzankov, N., 2019. Diversity and Distribution of Amphibians and Reptiles in the Bulgarian Part of the Lower Danube. — p. 283—314.
Zhelev, Z. M., Tsekov, A. G., Popgeorgiev, G. S., Angelov, M. V., Boyadzhiev, P. S., Stefanov, T. R., 2018. Ichthyofauna in the Lower Course of the Sazliyka River, Southern Bulgaria: Composition, Diversity, Seasonal Dynamics and Conservation Significance. — Acta zoologica bulgarica, 70 (3): 331—338.
Nedyalkov, N., Popgeorgiev, G., Staneva, A., 2018. Updated distribution of the elusive Roach’s mouse-tailed dormouse, Myomimus roachi Bate, 1937 (Mammalia: Rodentia: Gliridae) in Bulgaria. — Historia naturalis bulgarica, 29: 3—8. doi:10.48027/hnb.29.01001
Kornilev, Y. V., Popgeorgiev, G., Vacheva, E., Tzankov, N., 2018. First records of melanism (including in tail bifurcation) of lacertid lizards (Reptilia: Lacertidae) in Bulgaria. — North Western Journal of Zoology, 14 (1): 142—144.
Stefanov, T., Popgeorgiev, G., 2017. Distribution patterns and conservation status of the species from genus Alburnoides (Pisces, Cyprinidae) in Bulgaria. — Proceedings ISEM7, 69—76.
Koynova, T., Tzankov, N., Popgeorgiev, G., Naumov, B., Natchev, N., 2017. A new distribution record of the Kotschy’s Gecko (Mediodactylus kotschyi) from inland north-eastern Bulgaria. — Herpetology Notes 01/2017: 10: 1—2. [PDF]
Цанков, Н., Стоянов, А., Добрев, Д., Луканов, С., Корнилев, Ю., Андонов, К., Вергилов, В., Попгеоргиев, Г., 2017. Trachemys scripta (Thunberg in Schoepff, 1792). — стр. 110—113. В: Тричкова, Т., Владимиров, В., Томов, Р., Тодоров, М. (ред.): Атлас на инвазивните чужди видове от значение за Европейския съюз, ИБЕИ-БАН, ESENIAS, София, 176 стр. [PDF]
Cheshmedzhiev, S., Popgeorgiev, G., Petrov, T., Kornilev, Y., Spasov, S., Stoychev, S. (ed.), 2016. The White stork in Bulgaria in 2014 — 2015; — Bulgarian Society for the Protection of Birds, Sofia. p. 60. [PDF]
Tzankov, N., Popgeorgiev, G., Kornilev, Y., Petrov, B., Zidarova, S., Stefanov, T., 2015. Sofia. — In: Kelcey, J. (ed.), Vertebrates and Invertebrates of European Cities: Selected Non-Avian Fauna. Springer New York, 179—206.