Romanowski, Marcin, and Krzysztof Nadolny. “Methods of Graphical Analysis of Production Processes”. Journal of Mechanical and Energy Engineering 2, no. 1 (April 26, 2018): 33-42. Accessed March 20, 2019. http://jmee.tu.koszalin.pl/ojs/index.php/jmee/article/view/48.