Крихівський, Михайло Васильович, et al. “PROGRAMMING CALCULATION OF MODES COMPLEX GAS TRANSPORTATION SYSTEM”. PRECARPATHIAN BULLETIN OF THE SHEVCHENKO SCIENTIFIC SOCIETY. Number, no. 2(38), Feb. 2019, pp. 247-52, https://pvntsh.nung.edu.ua/index.php/number/article/view/49.