MacBook Pro 15" Retina Display Mid 2012 Teardown - iFixit
NEMIX RAM 16GB Kit (2x8GB Upgrade) DDR3-1600 SODIMM PC3-12800 for Apple MacBook Pro Mid 2012 / iMac Late 2012 / iMac 2013, Late 2014, Mid 2015, Mac Mini Late 2012 at Amazon.com
Replace your 2009-2012 MacBook Pro HD with an SSD
Apple macbook pro 13 inch mid 2012 (Maximum RAM and SSD Dual Storage Upgrade) | eBay
16GB 8GB 4GB DDR3 1600MHz RAM for Apple MacBook Pro Mid 2012 sodimm Memory lot | eBay
A-Tech 16GB Kit (2x8GB) RAM for Apple MacBook Pro (Mid 2012), iMac (Late 2012, Early/Late 2013, Late 2014, Mid 2015), Mac Mini (Late 2012) | DDR3 1600MHz PC3-12800 SODIMM 204-Pin Memory Upgrade at Amazon.com
MacBook Pro (13-inch, Mid 2012) Hard Drive (and possibly RAM) replacement : r/mac
How to Upgrade MacBook Pro RAM (2009, 2010, 2011, 2012): EveryMac.com
CMS 16GB (2X8GB) DDR3 12800 1600MHz Non ECC SODIMM Memory Ram Upgrade Compatible with Apple® MacBook Pro Core I7 2.3 15" Mid-2012 - A7
2012 Macbook Pro 15" A1286 RAM Upgrade - YouTube
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
Is upgrading the mid-2012 MacBook Pro Worth It? - Learn Robotics