1. 1. Bocko, B., et al., 2018: Book of the Pigeon Standards (In Slovak). Slovak Breeders Association, 1st edn., 315 pp.
2. 2. Bocko, B., 2014: European pigeon assessment system (In Slovak). Chovateľ (Breeder), 50, 6, 8.
3. 3. Dammers, R., 2019: Frills with a short beak at the European Exhibition 2018 in Herning (Germany). Mövchenpost. 90, 39—41.
4. 4. Domyan, E. T., Shapiro, M. D., 2017: Pigeonetics takes flight: Evolution, development, and genetics of intraspecific variation. Dev. Biol., 427, 2, 241—250. DOI: 10.1016/j.ydbio. 2016.11.008.
5. 5. EE, 2019: EE Documentation [Online] [cit. 2020-04-20]. Available at http://www.entente-ee.com/wp-content/uploads/EEDokumentation_August_2019_E.pdf>.