Ambarev, Krasimir, and Valyo Nikolov. “EXPERIMENTAL STUDY OF TOXIC COMPONENTS IN THE EXHAUST GASES DURING THE OPERATION OF A CAR ENGINE WITH GASOLINE AND LPG”. ENVIRONMENT. TECHNOLOGY. RESOURCES. Proceedings of the International Scientific and Practical Conference 3 (January 16, 2024): 20–23. Accessed April 16, 2025. https://journals23.rta.lv/index.php/ETR/article/view/7304.