Hui Zhao Qi-Wen Ran Jing Ma 0003 Li-Ying Tan Generalized prolate spheroidal wave functions associated with linear canonical transform. 3032-3041 2010 58 IEEE Trans. Signal Process. 6 https://doi.org/10.1109/TSP.2010.2044609 db/journals/tsp/tsp58.html#ZhaoRMT10