Laxmi Bachanalaya
Legally available public-domain books and openly licensed reading materials.
Theodore L. Thomas
Jack Sharkey
Alfred Coppel
Various
Lester Del Rey
Robert Moore Williams
Randall Garrett
Ivar Jorgensen
Harlan Ellison
G. G. Revelle
Kris Neville
Stephen Marlowe
J. C. Fussell
Julian F. Grow
Robert F. Young
Sam McClatchie
Aaron L. Kolom
George O. Smith
Allen Kim Lang
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.