Two Swiss F-5 Tiger fighter jets are parked behind four F/A-18 fighter jets during the REVITA 2014 exercise at an air base of the Swiss air force in Buochs May 14, 2014. Switzerland will vote on a ... more 
Two Swiss F-5 Tiger fighter jets are parked behind four F/A-18 fighter jets during the REVITA 2014 exercise at an air base of the Swiss air force in Buochs May 14, 2014. Switzerland will vote on a referendum regarding the purchase of new Saab Gripen fighter jets on May 18, 2014. REUTERS/Arnd Wiegmann (SWITZERLAND - Tags: MILITARY POLITICS TRANSPORT) less 
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Reuters | Photo By ARND WIEGMANN / REUTERS
Wed, May 14, 2014 7:15 AM EDT