How to Upgrade/Install Memory in a 21.5-inch iMac (Late 2012– Mid 2014) iMac14,1 iMac14,3 - 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
Install memory in an iMac - Apple Support
Install memory in an iMac - Apple Support
Memory Upgrades for iMac 27-Inch (2012 - Mid 2015)
Memory RAM Upgrade for Apple iMac 27-inch Late 2012 4GB/8GB DDR3 SODIMM | eBay
Install memory in an iMac - Apple Support
How To Upgrade RAM in a Mac | Macworld
Install memory in an iMac - Apple Support
iMac RAM upgrade: Here's an affordable way to improve multitasking - CNET
CMS 32GB (4X8GB) DDR3 12800 1600MHz Non ECC SODIMM Memory Ram Upgrade Compatible with Apple® iMac Core I7 3.4 27-Inch (Late 2012) - A6 at Amazon.com