Investigation of the Opportunity to Develop a Phase-Frequency Ultrasonic Measuring Converter for the speed of Natural Gas Flow in Closed Small Diameter Pipeline. Вісник ВПІ [Internet]. 2019 Oct. 31 [cited 2026 Oct. 11];(5):7-13. Available from: https://visnyk.vntu.edu.ua/index.php/visnyk/article/view/2405