MacBook Pro: How to remove or install memory - Apple Support
Still using a 2009 MacBook Pro, should I upgrade to the new M2 macs? : r/ macbookpro
USED APPLE MacBook Air 2009 (A1304) 13" Intel 2.13 GHz Core 2 Duo 2GB RAM 128SSD | eBay
How to Upgrade MacBook Pro RAM (2009, 2010, 2011, 2012): EveryMac.com
A-Tech 16GB Kit (2x8GB) DDR3 1066MHz / 1067MHz PC3-8500 SODIMM RAM for Apple MacBook (13 inch, Mid 2010), MacBook Pro (13 inch, Mid 2010), iMac (27 inch, Late 2009), Mac Mini (Mid 2010) at Amazon.com
A-Tech 16GB Kit (2x8GB) DDR3 1066MHz / 1067MHz PC3-8500 SODIMM RAM for Apple MacBook (13 inch, Mid 2010), MacBook Pro (13 inch, Mid 2010), iMac (27 inch, Late 2009), Mac Mini (Mid 2010) at Amazon.com