Wilczok , Grzegorz. 2006. Записки Горного института 167 (2), 179-80. https://pmi.spmi.ru/pmi/article/view/7991.

Wilczok , Grzegorz. 2006. “The Technical Investigations of Sprayers in Poland in Aspect of Protection of Natural Environment”. Journal of Mining Institute 167 (2), 179-80. https://pmi.spmi.ru/pmi/article/view/7991.