Waśkowska, A., J. Golonka, G. Machowski, and E. Pstrucha. “Potential Source Rocks in the Ropianka Formation of the Magura Nappe (Outer Carpathians, Poland) – Geochemical and Foraminiferal Case Study”. Geology, Geophysics and Environment, vol. 44, no. 1, Apr. 2018, p. 49, doi:10.7494/geol.2018.44.1.49.