"High Strength Chemical Vapor Deposited Graphene and Grain Boundaries". Gwan-Hyoung Lee, Ryan Cooper, Sung Joo An, Sunwoo Lee, Arend van der Zande, Nicholas Petrone, Alexandra G. Hammerberg, Changgu Lee, Bryan Crawford, Warren Oliver, Jeffrey W. Kysar, and James Hone. Science (May 30, 2013)