MacBook Pro: How to remove or install memory - Apple Support
Timetec 8GB KIT(2x4GB) Compatible for Apple DDR3 1067MHz / 1066MHz PC3-8500 CL7 for Mac Book, Mac Book Pro, iMac, Mac Mini (Late 2008, Early/Mid/Late 2009, Mid 2010) SODIMM Memory MAC RAM Upgrade
How to Upgrade MacBook Pro RAM (2009, 2010, 2011, 2012): EveryMac.com
MacBook Pro: How to remove or install memory - Apple Support
MacBook Pro: How to remove or install memory - Apple Support
MacBook Pro RAM Upgrades (Non-Retina) - OWC
8GB PC10600 DDR3 1333MHz SO-DIMM Memory Compatible with 2011 MacBook Pro, Mid 2010/2011 21.5" & 27" iMac Models, 2011 Mac Mini (OWC1333DDR3S8GB) at Amazon.com