"The Exploration of the Colorado River in 1869 and 1871–1872: Biographical Sketches and Original Documents of the First Powell Expedition of 1869 and the Second Powell Expedition of 1871–1872.
"The Exploration of the Colorado River in 1869 and 1871–1872: Biographical Sketches and Original Documents of the First Powell Expedition of 1869 and the Second Powell Expedition of 1871–1872.