00508nam a2200181Ia 4500 CTU_17764 210402s9999 xx 000 0 und d 621.3 M365 Marshall, James L. Introduction to signal theory James L. Marshall New York International Book Co 1965 Signal theories Nguyễn Quang Điền, Hải Trung tâm Học liệu Trường Đại học Cần Thơ