Velev, V. ., N. Arhangelova, D. . Nedeva, Z. Stoyanova, and A. . Popov. “HEAT – MECHANICALLY INDUCED STRUCTURE DEVELOPMENT IN PARTIALLY CRYSTALLINE POLYESTER FIBERS. INFLUENCE OF THE MECHANICAL STRESS: HEAT – MECHANICALLY INDUCED STRUCTURE DEVELOPMENT IN PARTIALLY CRYSTALLINE POLYESTER FIBERS. INFLUENCE OF THE MECHANICAL STRESS”. JOURNAL SCIENTIFIC AND APPLIED RESEARCH, vol. 13, no. 1, Mar. 2023, pp. 52-57, doi:10.46687/jsar.v13i1.239.