Joachim Heinrich Schuette
…(1903) The hawthorns of northeastern Wisconsin. Proc. Biol. Soc. Washington 16: 91-98. http://books.google.com/books?id=iSkUAAAAYAAJ&lpg=PA91&ots=iuUbBApyNP&dq=hawthorns%20of%20northeastern%20wisconsin&pg=PA91#v=onepage&q=hawthorns%20of%20northeastern%20wisconsin&f=false SOURCES: 1. Stafleu & Cowan (1985) Taxonomic Literature, 2nd edition, Volume 5: 365. 2. Data Portal….