How to Upgrade MacBook Pro RAM (2009, 2010, 2011, 2012): EveryMac.com
Timetec Hynix IC 16GB KIT(2x8GB) Compatible for Apple DDR3 1333MHz PC3-10600 for Early/Late 2011 13/15/17 inch MacBook Pro, Mid 2010 Mid/Late 2011 21.5/27 inch iMac, Mid 2011 Mac Mini(16GB KIT(2x8GB)) - Walmart.com -
MacBook Pro (13-inch Late 2011) Core i5 4gb RAM 500gb Storage, Computers & Tech, Laptops & Notebooks on Carousell
MacBook Pro 15" Unibody Early 2011 RAM Replacement - iFixit Repair Guide
How To: MacBook Pro Late 2011 Memory Upgrade - 16GB (2 X 8GB) : 6 Steps - Instructables
Apple MacBook Pro 2011 (Early) (Late) 13-inch 15-inch 17-inch MacBookPro8,1 MacBookPro8,2 MacBookPro8,3 SSD RAM OSX UPGRADE - ZD Laptop Service Centre
MacBook Pro 13" Unibody Early 2011 RAM Replacement - iFixit Repair Guide
Apple MacBook Pro 13 inch (Early 2011) - Intel Core i5 - Catawiki
Refurbished Apple MacBook Pro 8,1/i5-2415M/8GB RAM/320GB HDD/Intel HD 3000/ 13-inch/A (Early - 2011) - Mac4sale
Macbook Pro (Late 2011) Memory Upgrade - Apple Community
Apple Adds Early 2011 13-Inch MacBook Pro to Obsolete Products List - MacRumors