- Lower Silesian Voivodeship
| Grochowina, A., Gołębiowska, B., & Pieczka, A. (2012). Graftonite-sarcopside intergrowths in phosphate nodulas from pegmatite at Michałkowa, Sowie Mountains Block, SW Poland. Geology, Geophysics and Environment, 38(4), 477-478. Eligiusz Szełęg private collection |