1. Abramov, S.A., Search of rational solutions to differential and difference systems by means of formal series, Program. Comput. Software, 2015, vol. 42, no. 2, pp. 65–73.
2. Abramov, S.A., Gheffar, A., and Khmelnov, D.E., Rational solutions of linear difference equations: Universal denominators and denominator bounds, Program. Comput. Software, 2011, vol. 37, no. 2, pp. 78–86.
3. Gelfond, A.O., Calculus of Finite Differences, Hindustan Publ. Corp., 1971.
4. Stanley, R.P., Enumerative Combinatorics, Cambridge University Press, 2010.
5. Sadykov, T.M., On a multidimensional system of hypergeometric differential equations, Sib. Math. J., 1998, pp. 986–997.