Habibullin I., Zheltukhina N., Sakieva A., “On Darboux-integrable semi-discrete chains”, Journal of Physics A-Mathematical and Theoretical, 43:43 (2010), 434017
Habibullin I., Zheltukhina N., Pekcan A., “Complete list of Darboux integrable chains of the form $t_{1x}=t_x+d(t,t_1)$”, J. Math. Phys., 50:10 (2009), 102710, 23 pp.
Habibullin I., Pekcan A., Zheltukhina N., “On some algebraic properties of semi-discrete hyperbolic type equations”, Turkish J. Math., 32:3 (2008), 277–292
Habibullin I., Zheltukhina N., Pekcan A., “On the classification of Darboux integrable chains”, J Math Phys, 49:10 (2008), 102702