We can see here, over 50mil papers. http://libgen.io/scimag/repository_torrent_notforall/ http://libgen.io/scimag/repository_torrent_notforall/ As you can see

We can see here, over 50mil papers. http://libgen.io/scimag/repository_torrent_notforall/ http://libgen.io/scimag/repository_torrent_notforall/ As you can see here, they have three mirrors. One Moscow, one Ocean(ia?), and one Cyber(ia?). Libgen also has a mirror. As for BookSC, they seem to be quite a bit out of date, or something.