___

• Blain H-A, Lozano-Fernandez I, Bohme G (2015). Variation in the ilium of central European water frogs Pelophylax (Amphibia, Ranidae) and its implications for species-level identification of fragmentary anuran fossils. Zoological Studies 54 (1): 5. doi: 10.1186/s40555-014-0094-3
• Bucci S, Ragghianti M, Guerrini F, Cerrini V, Mancino G et al. (2000). Negative environmental factors and biodiversity: the case of the hybridogenetic green frog system from Lake Trasimeno. Italian Journal of Zoology. 67 (4): 365-370. doi: 10.1080/11250000009356341
• Curnutt JL, Pimm SL, Maurer BA (1996). Population variability of sparrows in space and time. Oikos 76 (1): 131-144. doi: 10.2307/3545755
• Darroch JN, Mosimann JE (1985). Canonical and principal components of shape. Biometrika 72 (2): 241-252.
• Dedukh DV, Krasikova AV (2017). Methodological approaches for studying the European water frog Pelophylax esculentus complex. Russian Journal of Genetics 53 (8): 843-850. doi: 10.1134/S102279541708004X
• Dillon WR, Goldstein M (1984). Multivariate Analysis–Methods and Applications. New York, NY, USA: Wiley.
• Dubois A, Günther R (1982). Klepton and synklepton: two new evolutionary systematics categories in zoology. Zoologische Jahrbücher, Abteilung für Systematik, Ökologie und Geographie der Tiere 109 (2): 290-305.
• Džukić G, Kalezić M, Ljubisavljević K, Krizmanić I (2001). The integrative analysis of the exploitation of the green frogs in SR Yugoslavia. The Final Reports I & II. Federal Secretariat of
• Labour, Health and Social Care, Serbia: 99 (in Serbian) Escofier B, Pagès J (2008). Analyses factorielles simples et multiples, Objectifs, methods et interprétation. Paris, France: Dunod (in French).
• Gubányi A, Korsós Z (1992). Morphological analysis of two Hungarian water frog (Rana lessonae-esculenta) populations. Amphibia-Reptilia 13 (3): 235-243.
• Günther R (1990). Die Wasserfrösche Europas. Die Neue Brehm Bücherei 600. Ziemsen, Wittenberg Lutherstadt (in German).
• Günther R, Plötner J (1994). Morphometric, enzymological and bioacoustic studies in Italian water frogs (Amphibia, Ranidae). Zoologica Poloniae 39 (3-4): 287-415.
• Günther R, Plötner J, Tetzlaff I (1991). Zu einigen Merkmalen der Wasserfrösche (Rana synkl. esculenta) des Donau–Deltas. Salamandra 27 (4): 246-265 (in German).
• Hotz H, Uzzell T (1982). Biochemical detected sympatry of two water frog species: Two different cases in the Adriatic Balkans (Amphibia: Ranidae). Proceedings of the Academy of Natural Sciences of Philadelphia. 134: 50-79.
• Husson F, Josse J, Le S, Mazet J (2010). FactoMineR: multivariate exploratory data analysis and data mining with R.
• Jungers WL, Falsetti AB, Wall CE (1995). Shape, relative size, and size-adjustments in morphometrics. Yearbook of Physical Anthropology 38: 137-161.
• Karaman SL (1948). Prilog herpetologiji sjeverne Srbije. Prirodoslovna istraživanja Jugoslavenska akademija znanosti i umjetnosti, 24: 51-73 (in Serbo-Croatian).
• Kierzkowski P, Kosiba P, Rybacki M, Socha M, Ogielska M (2013). Genome dosage effect and coloration features in hybridogenetic water frogs of the Pelophylax esculentus complex. AmphibiaReptilia 34 (4): 493-504. doi: 10.1163/15685381-00002904
• Kierzkowski P, Pasko L, Rybacki M, Socha M, Ogielska M (2011). Genome dosage effect and hybrid morphology – the case of the hybridogenetic water frog of the Pelophylax esculentus complex. Annales Zoologici Fennici 48 (1): 56-66. doi: 10.5735/086.048.0106
• Krizmanić I (2008a). Water frogs (Rana esculenta complex) in Serbia– morphological data. The Archives of Biological Sciences 60 (3): 449-457. doi: 10.2298/ABS0803449K
• Krizmanić I (2008b). Basic morphological characteristics of the Rana (Pelophylax) synklepton Esculenta complex in relation to legal regulations in Serbia. Archives of Biological Sciences 60 (4): 629-639. doi: 10.2298/ABS0804629K
• Krizmanić I (2015). Pelophylax lessonae. In „Crvena knjiga faune Srbije I – Vodozemci” Ed by Kalezić et al. Biološki fakultet & Zavod za zaštitu prirode Srbije, Beograd, pp. 179-185 (in Serbian).
• Krizmanić I, Ivanović A (2010). Population systems of the Pelophylax complex in the southern part of its range. Folia Zoologica 59 (3): 215-222. doi: 10.25225/fozo.v59.i3.a7.2010
• Kuzmin S, Beebee T, Andreone F, Nyström P, Anthony BP et al. (2009). Pelophylax lessonae (errata version published in 2016). The IUCN Red List of Threatened Species.
• Lê S, Josse J, Husson F (2008). FactoMineR: an R package for multivariate analysis. Journal of Statistical Software 25: 1-18.
• Marracci S, Michelotti V, Guex G-D, Hotz H, Uzzell T et al. (2011). RrS1-like sequences of frogs from central Europe and around the Aegean Sea: chromosomal organization, evolution, possible function. Journal of Molecular Evolution 72 (4): 368-382. doi: 10.1007/s00239-011-9436-5
• Mayer M, Hawlitschek O, Zahn A, Glaw F (2013). Composition of twenty green frog populations (Pelophylax) across Bavaria, Germany. Salamandra 49 (1): 31-44.
• McCarthy DM, Mason-Gamer RJ (2019). Morphological variation in North American Tilia and its value in species delineation. International Journal of Plant Sciences. doi: 10.1086/706781
• Mikulíček P, Kautman M, Kautman J, Pruvost NBM (2014). Mode of hybridogenesis and habitat preferences influence population composition of water frogs (Pelophylax esculentus complex, Anura: Ranidae) in a region of sympatric occurrence (western Slovakia). Journal of Zoological Systematics and Evolutionary Research, 53 (2): 124-132. doi: 10.1111/jzs.12083
• Nekrasova O, Mezhzherin S, Morozov-Leonov S (2003). Diagnostic traits in the morphology of green frogs (Rana esculenta complex) in the Middle Dnieper Basin. In: “Herpetologia Petropolitana” Proceedings of the 12th Ordinary General Meeting of Societas Europaea Herpetologica; St. Petersburg, Russia. pp. 77-79.
• Ogielska M, Kierzkowski P, Rybacki M (2004). DNA content and genome composition of diploid and triploid water frogs belonging to the Rana esculenta complex (Amphibia, Anura). Canadian Journal of Zoology 82 (12): 1894-1901. doi: 10.1139/ z04-188
• Pagano A, Joly P (1999). Limits of the morphometric method for field identification of water frogs. Alytes 16 (3-4): 130-138.
• Pagès J, Camiz S (2008). Analyse factorielle multiple de données mixtes: application à la comparaison de deux codages. La Revue de Modulad 38: 178-183 (in French).
• Plötner J, (2005). Die westpaläarktischen Wasserfrösche: von Märtyrern der Wissenschaft zur biologischen Sensation. Laurenti, Bielefeld (in German).
• Polls-Pelaz M (1989). The biological klepton concept (BKC). Alytes 8 (3): 75-89.
• Ragghianti M, Bucci S, Marracci S, Casola C, Mancino G et al. (2007). Gametogenesis of intergroup hybrids of hemiclonal frogs. Genetics Research 89 (1): 39-45. doi: 10.1017/ S0016672307008610
• Ragghianti M, Guerrini F, Bucci S, Mancino G, Hotz H et al. (1995). Molecular characterization of a centromeric satellite DNA in the hemiclonal hybrid frog Rana esculenta and its parental species. Chromosome Research 3 (8): 497-506. doi: 10.1007/ BF00713965
• Rybacki M (1995). Water frogs (Rana esculenta complex) of the Bornholm Island. Denmark. Zoologica Poloniae 39 (3-4): 331-344.
• Spasić Bošković O, Krizmanić I, Vujošević M (1999). Population composition and genetic variation of water frogs (Anura: Ranidae) from Yugoslavia. Caryologia 52 (1-2): 9-20. doi: 10.1080/00087114.1998.10589148
• Stanchak KE, Santana SE (2019). Do ecogeographical rules explain morphological variation in a diverse, Holarctic genus of small mammals? Journal of Biogeography 46 (1): 110-122. doi: 10.1111/jbi.13459
• Tognarelli G, Zuffi M, Marracci S, Ragghianti M (2014). Surveys on populations of green frogs (Pelophylax) of Western Tuscany sites with molecular and morphometric methods. Amphibia– Reptilia 35 (1): 99-105. doi: 10.1163/15685381-00002931
• Tosunoğlu M, Ayaz D, Göçmen B (2005). On Specimens of Rana ridibunda Pallas, 1771 (Anura: Ranidae) Collected from Yağmapınar (Karapınar Konya). Anadolu University Journal of Science and Technology 6 (1): 55-59.
• Uzzell T, Berger L (1975). Electrophoretic phenotypes of Rana ridibunda, Rana lessonae and their hybridogenetic associate, Rana esculenta. Proceedings of the Academy of Natural Sciences of Philadelphia 127: 13-24.
• Uzzell T, Berger L, Günther R (1975). Diploid and triploid progeny from a diploid female of Rana esculenta (Amphibia, Salientia). Proceedings of the Academy of Natural Sciences of Philadelphia 127: 81-91.
• Venables WN, Ripley BD (2002). Modern Applied Statistics with S-plus. 4th ed. New York, NY, USA: SpringerVerlag.
• Vucetich JA, Waite TA (2003). Spatial patterns of demography and genetic processes across the species’ range: null hypotheses for landscape conservation genetics. Conservation Genetics 4 (5): 639-645. doi:10.1023/A:1025671831349
• Vukov T, Kalezić M, Tomović L, Krizmanić I, Jović D et al. (2013). Amphibians in Serbia: distribution and diversity patterns. Bulletin of the Natural History Museum 6: 90-112. doi:10.5937/ bnhmb1306090V
• Vukov T, Tomović LJ, Krizmanić I, Labus N, Jović D et al. (2015). Conservation issues of Serbian amphibians identified from distributional, life history and ecological data. Acta Zoologica Bulgarica 67 (1): 105-116.
• Whelan NV, Galaska MP, Sipley BN, Weber JM, Johnson PD et al. (2019). Riverscape genetic variation, migration patterns, and morphological variation of the threatened Round Rocksnail, Leptoxis ampla. Molecular ecology 28 (7): 1593-1610. doi: 10.1111/mec.15032