1940, Dunkerque stamps, superb letter franked with Y&T n° 3 in block of four (two pairs holding each other) and n° 4 also in block of four (two pairs holding each other), very beautiful Dunkerque cancels 01/07/1940 of the first day of issue (these overprinted stamps were used from 01/07 until 09/08/1940). Very fine piece, signed Pickenpack and Scheller, ex. Weinman-Lays.