Titlebook: Coherent States, Wavelets, and Their Generalizations; Syed Twareque Ali,Jean-Pierre Antoine,Jean-Pierre Book 2014Latest edition Springer

Hemiparesis

Positive Operator-Valued Measures and Frames,start with continuous frames and introduce two generalizations, called upper, resp. lower, semi-frames, for which only the upper, resp. lower, frame bound is satisfied. Then we turn to the more familiar discrete frames and their generalizations.