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
Fixxo - MacBook RAM Upgrade | Do more with your Old Mac
M1 Mac RAM and SSD Upgrades Found to Be Possible After Purchase - MacRumors
How to upgrade RAM on MacBook (M1 & M2 Macs included)