Columbia subject headings:
Colorado--Description and travel.
Gold mines and mining--Colorado.
Gold mines and mining--Kansas.
Gold mines and mining--Nebraska.
Pikes Peak (Colo.)
Harvard subject headings:
Colorado--Description and travel.
Gold mines and mining--Colorado
Gold mines and mining--Kansas.
Gold mines and mining--Nebraska.
Pikes Peak (Colo.)
Princeton subject headings:
Colorado--Description and travel.
Pikes Peak (Colo.)