EX-10.17 18 ex10-17.htm FIFTEENTH AMENDMENT TO PROMISSORY NOTES DATED AS OF APRIL 20, 2012 AMONG GROEN BROTHERS AVIATION, INC. AND LENDER A NAMED THEREIN ex10-17.htm
Exhibit 10.17
 
 
1
 
 
 
2
 
 
 
3
 
 
 
4
 
 
5