Запухляк, І. Б. 2014. “Components of the Environment of Functioning and Development of the National Gas Transportation Enterprises”. Scientific Bulletin of Ivano-Frankivsk National Technical University of Oil and Gas (Series: Economics and Management in the Oil and Gas Industry) 1 (9):55-61. https://eung.nung.edu.ua/index.php/ecom/article/view/191.