Laxmi Bachanalaya
Legally available public-domain books and openly licensed reading materials.
George P. Marsh
Harold W. Fairbanks
Gifford Pinchot
Murat Halstead
C. Reginald Enock
Illinois State Geological Survey
Joseph Corry
George Gardner
L. H. Bailey
Ithamar M. Howell
Mayne Reid
United States. National Conservation Congress
Sir Horace Curzon Plunkett
Franklin K. Lane
Ernest J. Chambers
Mary Huston Gregory
C. H. Forbes-Lindsay
Canada. National Parks Branch
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.