Laxmi Bachanalaya
Legally available public-domain books and openly licensed reading materials.
Augustus De Morgan
Robert Record
Felix Klein
Gino Loria
Henry Parker Manning
Hendrik Sluijters
Thomas Hobbes
Lyon Des Roys
James Bell Salmond
Rudolf Rothe
Euclid, Raymond Clare Archibald, Franz Woepcke, and Leonardo Fibonacci
Archimedes
Paul Carus
Lewis Carroll
Alexis-Claude Clairaut
Theodor Reye
H. Laurent
Ernest Vessiot
Johannes Frischauf
Albert Ribaucour
Otto Bohler
Wolfgang Vogt
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.