ペール・アクセル・リュードベリ
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, Colorado, Utah, Wyoming, Idaho, Montana, Saskatchewan, Alberta, and neighboring parts of Nebraska, South Dakota, and British Columbia