Books by Otis E. Gahm:
Books in the extended shelves:
![[X-Info]](https://onlinebooks.library.upenn.edu/infouc.gif)
Gahm, Otis E.: Manual of mushroom culture (Chester county mushroom laboratories, 1941), also by West Chester Chester county mushroom laboratories, Floyd W. Divine, and Granville Raymond Rettew (page images at HathiTrust)
Find more by Otis E. Gahm at your library, or elsewhere.