Leaders of American conservation / edited by Henry Clepper.

od Clepper, Henry, 1901-1987.
Izdano 1971

Origins of American conservation / Edited for the Natural Resources Council of America by Henry Clepper.

od Clepper, Henry, 1901-1987.
Izdano 1966

Careers in conservation : opportunities in natural resource management / edited for the Natural Resources Council of America by Henry Clepper.

od Clepper, Henry, 1901-1987.
Izdano 1979

Hemlock : the state tree of Pennsylvania / by Henry E. Clepper.

od Clepper, Henry, 1901-1987.
Izdano 1944

Professional forestry in the United States / [by] Henry Clepper.

od Clepper, Henry, 1901-1987.
Izdano 1971