Z. Khokerashvili and D. Tsanava, “Propagation of carbon monoxide in road tunnels in case of fire by considering the critical velocity, backlayering and gradient factor : Print version was published: Book of Abstract, The International Scientific and Technical Conference: ‘Problems of Engineering Sciences ’ Yerevan University of International Relations named after A. Shirakatsi Yerevan - Republic of Armenia, May 20-22, 2022”, GS, vol. 4, no. 3, pp. 63–65, May 2022.