Rahimi, A., M. H. Faroughi, and M. R. Abdollahpour. “$pg$-Frame in Banach Spaces”. Methods of Functional Analysis and Topology 13, no. 3 (September 25, 2007): 201–210. Accessed February 4, 2026. https://zen.imath.kiev.ua/index.php/mfat/article/view/349.