On the duality of c-fusion frames in Hilbert spaces
  Improving and extending the concept of dual for frames, fusion frames and continuous frames, the notion of dual for continuous fusion frames in Hilbert spaces will be studied. It will be shown that generally the dual of c-fusion frames may not be defined. To overcome this problem, the new concept namely Q-dual for c-fusion frames will be defined and some of its properties will be investigated. 
Asghar Rahimi, Zahra Darvishi and Bayaz Daraby
math.FA