Upgrade Your Macbook Pro (SSD Upgrade, RAM Upgrade, Optical Drive Bay Adapter) - YouTube
Amazon.com: Odyson - Logic Board 2.3GHz i7, 16GB Replacement for MacBook Pro 15" Retina A1398 (Mid 2012, Early 2013) : Electronics
Buy Macbook Pro Mid 2012 Memory | UP TO 58% OFF
mac - What is the maximum RAM size for MacBook Pro Mid 2012? - Ask Different
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
Adamanta 16GB (2x8GB) Apple Memory Upgrade DDR3L 1600MHz SODIMM Compatible for iMac (Mid 2011, Late 2012, Early/Late 2013, Late 2014, Mid 2015), MacBook Pro (Early/Late 2011, Mid 2012), Mac Mini at Amazon.com
16GB MacBook Pro RAM Upgrade (2011/2012/2013) - YouTube