Njagi, L., B. M. Nzimbi, and S. K. Moindi. 2018. “On Finite Dimensional Hilbert Space Frames, Dual and Normalized Frames and Pseudo-Inverse of the Frame Operator”. Journal of Advance Research in Mathematics And Statistics 5 (11):01-10. https://doi.org/10.53555/nnms.v5i11.528.