(1974). Map showing potential sources of gravel and crushed-rock aggregate in the Colorado Springs-Castle Rock area, Front Range urban corridor, Colorado. U.S. Geological Survey.
Chicago-Zitierstil (17. Ausg.)Map Showing Potential Sources of Gravel and Crushed-rock Aggregate in the Colorado Springs-Castle Rock Area, Front Range Urban Corridor, Colorado. Reston, Va: U.S. Geological Survey, 1974.
MLA-Zitierstil (9. Ausg.)Map Showing Potential Sources of Gravel and Crushed-rock Aggregate in the Colorado Springs-Castle Rock Area, Front Range Urban Corridor, Colorado. U.S. Geological Survey, 1974.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.