Found 3 comments on HN
ZeroGravitas · 2016-05-04 · Original thread
Also re-issued recently for those who prefer physical books:

mrcactu5 · 2013-12-31 · Original thread
Works from 1916 and before are public domain? Not a bad start.

It is a really great to read the beautiful color version of the *First Six Books of the Elements of Euclid" online for free.

Meanwhile it is selling on Amazon for up to $100

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