Laxmi Bachanalaya
Legally available public-domain books and openly licensed reading materials.
Robert Record
Henry Parker Manning
Thomas Hobbes
Augustus De Morgan
James Bell Salmond
Archimedes
Euclid, Raymond Clare Archibald, Franz Woepcke, and Leonardo Fibonacci
Felix Klein
Paul Carus
Lewis Carroll
These books are free to read. Each is in the public domain in the United States; check your own country's rules before you copy or share one.