How To: MacBook Pro Late 2011 Memory Upgrade - 16GB (2 X 8GB) : 6 Steps - Instructables
How to Upgrade RAM on a 2019 MacBook Pro
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Upgrading RAM in Your MacBook Pro 13" or 15" : 19 Steps (with Pictures) - Instructables
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MacBook Pro 13" Unibody Early 2011 RAM Replacement - iFixit Repair Guide