A-Tech 8GB RAM for Apple MacBook Pro (Mid 2012), iMac (Late 2012, Early/Late 2013, Late 2014, Mid 2015), Mac Mini (Late 2012) | DDR3 1600MHz SODIMM PC3-12800 204-Pin SO-DIMM Memory Upgrade at Amazon.com
Apple MacBook Pro with Retina Display (15-inch, 2014) review: Still the best higher-res laptop, but the competition is catching up - CNET
How to Upgrade the SSD on a MacBook Pro Retina Early/Mid/Late 2013/2014/2015 - Replacement Tutorial - YouTube
MacBook Pro (Retina, 13-inch, Early 2015) Upgrade to NVMe M.2 SSD - YouTube
Review: Apple's mid-2014 13-inch MacBook Pro with Retina display | AppleInsider
SSD Upgrades for 2013, 2014, and 2015 MacBook Pro
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
macbook pro - Can I upgrade RAM on late 2013 retina Mac Book Pro? - Ask Different
A-Tech for Apple 16GB Kit (2x 8GB) DDR3 1600MHz PC3-12800 204-pin SODIMM MacBook Pro (Mid 2012 13”/15”), iMac (Late 2012, Early/Late 2013, Late 2014, Mid 2015, 21.5”/27”, Retina 5K) Memory RAM Upgrade at Amazon.com
15" 15 Inch Retina MacBook Pro A1398 Mid 2015 Complete Disassembly (Almost) SSD Upgrade - YouTube
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