U.S. President Barack Obama (C) is accompanied by Swedish Prime Minister Fredrik Reinfeldt (L) as he speaks to Professor Goran Lindberg (R) during a visit to an energy expo event at the Royal ... more 
U.S. President Barack Obama (C) is accompanied by Swedish Prime Minister Fredrik Reinfeldt (L) as he speaks to Professor Goran Lindberg (R) during a visit to an energy expo event at the Royal Institute of Technology-Campus Library in Stockholm, September 4, 2013. REUTERS/Fredrik Persson/Scanpix Sweden (SWEDEN - Tags: POLITICS SCIENCE TECHNOLOGY ENERGY) ATTENTION EDITORS - THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY. IT IS DISTRIBUTED, EXACTLY AS RECEIVED BY REUTERS, AS A SERVICE TO CLIENTS. SWEDEN OUT. NO COMMERCIAL OR EDITORIAL SALES IN SWEDEN less 
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Reuters | Photo By SCANPIX SWEDEN / REUTERS
Wed, Sep 4, 2013 11:57 AM EDT