@book{bhlitem40750, title = {North American trees (exclusive of Mexico and tropical United States) A handbook designed for field use }, copyright = {No known copyright restrictions as determined by scanning institution}, url = {https://www.biodiversitylibrary.org/item/40750}, note = {https://www.biodiversitylibrary.org/bibliography/10186}, publisher = {Ames, Iowa State University Press, [1961]}, author = {Preston, Richard Joseph,}, year = {1961}, pages = {440}, keywords = {Canada|Identification|Trees|United States|}, }