How to upgrade the memory in a Non-Retina 15-inch MacBook Pro 2011-2016 MacBookPro8,1 MacBookPro9,1 - YouTube
iFixit Launches Repair Guides for Retina MacBook Pro - MacRumors
MacBook Pro: How to remove or install memory - Apple Support
Amazon.com: 4 GB de memoria RAM certificado para Apple MacBook Pro 15-inch Core i7 2,2 gHz Late 2011 (MD318LL/A) DDR3 modelo Rank 1 memoria por arco memoria : Electrónica
Apple MacBook Pro 15 High Performance Core i7 2.5GHz, 8GB RAM, 256GB SSD - Megazone