Collected Papers of Albert Einstein available on Open Access site
Princeton University Press has made the Collected Works of Albert Einstein digitally available on an Open Access site:
https://ejournalscambridge.wordpress.com/2015/05/29/the-collected-papers-of-albert-einstein/
https://ejournalscambridge.wordpress.com/2015/05/29/the-collected-papers-of-albert-einstein/