Heimann et al., 1997. University of Wisconsin, Extension Cooperative Extension, A3182 Document reference Heimann, M. F. ; Stevenson, W. R., 1997. Walnut and butternut toxicity. University of Wisconsin, Extension Cooperative Extension, A3182Web http://learningstore.uwex.edu/Walnut-and-Butternut-Toxicity-P390.aspxCitation key Heimann et al., 1997Datasheets Walnut (Juglans regia)