Synthesis and optical properties of new photochromic systems based on 1,2-bis(2-methylbenzo[b]thien-3-yl) hexafluorocyclopentenes and 5,7-dihydro-1H-1,2,5,7,8-pentaaza-s-indacen-6-one or 1,7-dihydro-5-thia-1,2,7,8- tetraaza-s-indacen-6-one derivatives [Electronic resource] / M. M. Krayushkin, A. M. Bogacheva, A. N. Komogortsev, B. V. Lichitsky, A. A. Dudinov, K. S. Levchenko, O. I. Kobeleva, T. M. Valova, V. A. Barachevskii, V. N. Charushin // Journal of Sulfur Chemistry. - 2013. - Vol.34, №6. - С. 580-587. - Bibliogr. : p. 587 (15 ref.). - Режим доступа: http://www.tandfonline.com/doi/pdf/10.1080/17415993.2013.822500. - (Дата обращения: 19.03.2014)