MacBook Pro 2012 13'' RAM (Memory) Upgrade - YouTube
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
How to upgrade the memory in a Non-Retina 15-inch MacBook Pro 2011-2016 MacBookPro8,1 MacBookPro9,1 - YouTube
Memory RAM Upgrades for MacBook Pro (2012 - Late 2016)