Guliy, V., et al. “Calclithites of the Krosno Zone in the East Carpathians (Ukraine)”. Visnyk of Taras Shevchenko National University of Kyiv. Geology, vol. 4, no. 79, Dec. 2017, pp. 6-11, https://doi.org/10.17721/1728-2713.79.01.