Brickle, T., E. Bátor, and Zs. Halász. “Algebraic Description of Technical Chemical Systems II. Material Systems And Changes”. Hungarian Journal of Industry and Chemistry 1, no. 2 (March 2, 1973): 163–184. Accessed May 16, 2024. https://hjic.mk.uni-pannon.hu/index.php/hjic/article/view/527.