Shopova, E.; Mihailova, B.; Drumeva-Yoncheva, M.; Todorova, D.; Sergiev, I.; Yonchev, Y. Comparative Study of Drought Tolerance of Virginia Tobacco Genotypes Differing in Origin and Their Corresponding Hybrid Progenies. C. R. Acad. Bulg. Sci. 2022, 75, 1540-1548.