Author:Per Axel Rydberg

Works

 * 1895: Flora Of The Sand Hills Of Nebraska
 * 1897: A Report Upon the Grasses and Forage Plants of the Rocky Mountain Region with C. L. Shear
 * 1898: A Monograph of the North American Potentilleae
 * 1900: Catalogue of the Flora of Montana and the Yellowstone National Park
 * 1906: Flora of Colorado
 * 1917: Flora of the Rocky Mountains and Adjacent Plains
 * 1918: Monograph on Rosa
 * 1923: Flora of the Black Hills of South Dakota
 * 1923: Memories from the Department of Botany of Columbia University
 * 1932: Flora of the Prairies and Plains of Central North America with M. A. Howe