Hakopian, Yu.R., and S.S. Aleksanyan. “MOORE–PENROSE INVERSE OF BIDIAGONAL MATRICES. I”. Proceedings of the YSU A: Physical and Mathematical Sciences, vol. 49, no. 2 (237), June 2015, pp. 11-20, doi:10.46991/PSYU:A/2015.49.2.011.