http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
variability of paper birch, seed production, dispersal, and germination
by John C. Bjorkbom, David A. Marquis, Frank E. Cunningham.
Includes bibliographical references (pages 7-8).
Upper Darby, Pa. : Northeastern Forest Experiment Station, Forest Service, U.S. Dept. of Agriculture, 1965
U.S. Forest Service research paper NE ; 41