Reference

Curtis J. Richardson, Greg J. Koerper (1981): The Influence of Edaphic Characteristics and Clonal Variation on Quantity and Quality of Wood Production in Populus grandidentata Michx. in the Great Lakes Region of the U.S.A. – Mitteilungen der forstlichen Bundes-Versuchsanstalt Wien – 142_2_1981: 271 - 292.