Vöth , Stefan, и M. A. Vasilyeva. 2016. "Properties That Determine the Efficiency and Safety of Form Fitting Safety Couplings". Записки Горного института 219 (июнь), 455-58. https://doi.org/10.18454/pmi.2016.3.455.

Vöth , Stefan, and M. A. Vasilyeva. 2016. "Properties That Determine the Efficiency and Safety of Form Fitting Safety Couplings". Journal of Mining Institute 219 (June), 455-58. https://doi.org/10.18454/pmi.2016.3.455.