I've been meaning for some time to highlight the above series of books on the aviation aspects of the Normandy invasions by Martin Bowman. The anniversary of D-Day seems an excellent time to do so.
Sadly events have overtaken me and these volumes have proved popular even without the plug: although I have several copies of Winged Pegasus and The Rangers, I only have one full five-volume set left.
Bowman has written a similar series on Operation Market Garden. Of that set, I only have copies of Volume 1 and Volume 3. Time to restock soon, I think!
These, and other copies of Bowman's work (must-reads for anyone interested in World War II in the air) can be seen here.