macbook pro - Can I upgrade RAM on late 2013 retina Mac Book Pro? - Ask Different
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Add more RAM to your MacBook Pro (photos) - CNET
Used Apple MacBook Pro 13.3-inch Laptop 2014 MGXD2LL/A, 3.0 GHz Intel Core i7, 8GB RAM, MacOS, 512GB SSD, Grade B - Silver - Walmart.com
MacBook Pro 13" Retina (Mid 2014) 2.6 GHz Logic Board