Amazon.com: Timetec 16GB KIT(2x8GB) Compatible for Apple DDR3 1333MHz PC3-10600 CL9 for Mac Book Pro (Early/Late 2011 13/15/17 inch), iMac(Mid 2010, Mid/Late 2011 21.5/27 inch), Mac Mini(Mid 2011) MAC RAM Upgrade :
How to Upgrade MacBook Pro RAM (2009, 2010, 2011, 2012): EveryMac.com
How to Upgrade MacBook Pro RAM (2009, 2010, 2011, 2012): EveryMac.com
MacBook Pro 13" Unibody Late 2011 RAM Replacement - iFixit Repair Guide
MacBook Pro 15" Unibody Late 2011 RAM Replacement - iFixit Repair Guide
OWC 16GB (2x8GB) ram Upgrade PC3-12800 DDR3L 1600MHz sodimm 204 Pin CL11 Memory Upgrade Kit Compatible with Late iMac, Mac Mini, and MacBook Pro Computer at Amazon.com
MacBook Pro 13" Unibody Late 2011 RAM Replacement - iFixit Repair Guide
A-Tech 16GB (2x8GB) RAM for Apple MacBook Pro (Early/Late 2011), iMac (Mid 2010 27 inch 4-Core, Mid 2011 21.5/27 inch), Mac Mini (Mid 2011) | DDR3 1333MHz PC3-10600 204-Pin SODIMM Memory Upgrade Kit at Amazon.com
DDR3 12800S PC3L-1600MHz 16GB Kit (2x8GB) 2Rx8 1.35V CL11 Notebook RAM Memory for Early/Mid/Late 2011, Mid/Late 2012, Early/Late 2013, Late 2014, Mid 2015 MacBook Pro, iMac, Mac Mini at Amazon.com
Memory/ RAM Upgrades For Apple MacBook Pro 2011 from OWC
How to Upgrade RAM on MacBook Pro, iMac & More | AVG
MacBook Pro: How to remove or install memory - Apple Support
How to Upgrade MacBook Pro RAM (2009, 2010, 2011, 2012): EveryMac.com
MacBook Pro 13" Unibody Late 2011 RAM Replacement - iFixit Repair Guide
How To: MacBook Pro Late 2011 Memory Upgrade - 16GB (2 X 8GB) : 6 Steps - Instructables
MacBook Pro 13" Unibody Late 2011 RAM Replacement - iFixit Repair Guide
MacBook Pro: How to remove or install memory - Apple Support
MacBook Pro 15" Unibody Late 2011 RAM Replacement - iFixit Repair Guide
MacBook Pro 13" Unibody Late 2011 RAM Replacement - iFixit Repair Guide
Display Quality & Peripherals - Apple 15-inch MacBook Pro (Late 2011) Review