https://digitalcollections.lib.iastate.edu/haydenada/items/haydenada396.html
Letter from C.E. Allen to Louis Hermann Pammel, August 15, 1918 | Ada Hayden Collection
Item from Ada Hayden Collection: Letter from C.E. Allen to Louis Hermann Pammel, concerning the publication of a paper by Ada Hayden.
https://digitalcollections.lib.iastate.edu/haydenada/items/haydenada397.html
Letter from Louis Hermann Pammel to S. W. Beyer, November 21, 1919 | Ada Hayden Collection
Item from Ada Hayden Collection: Letter from Louis Hermann Pammel to S. W. Beyer, describing an enclosed letter from J. N. Martin that compliments Ada Hayden's...
https://digitalcollections.lib.iastate.edu/carver/items/carver125.html
George W. Carver letter to L. H. Pammel, July 15, 1921 | George Washington Carver Collection
Item from George Washington Carver Collection.
https://digitalcommons.usf.edu/wilson_bulletin/vol40/iss4/14/
"The Pollination of Scarlet Sage Flowers by Hummingbirds" by L. H. Pammel
By L. H. Pammel, Published on 12/01/28
scarlet sagepollination
https://digitalcollections.lib.iastate.edu/haydenada/items/haydenada545.html
Letter from Ada Hayden to Louis Hermann Pammel | Ada Hayden Collection
Item from Ada Hayden Collection: Letter from Ada Hayden to Louis Hermann Pammel, updating Pammel on her work in Houston, Texas.
letteradahaydenlouishermann