1930 Graf Zeppelin complete FDC's. One cover with C13 block of 4, the other cover with C14 & C15, both postmarked Washington, D.C., April 19 1930, the day of issue, then later flown on the Europe Pan-American Flight with appropriate red & purple cachets; stamps nicely cancelled, a Very Fine set. Scott No. C13-C15  $3,500. $0 (Image)