Não informado. The Mountain Geologist. Rocky Mountain Association of Geologists.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. The Mountain Geologist. Denver, Colo: Rocky Mountain Association of Geologists.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. The Mountain Geologist. Rocky Mountain Association of Geologists.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.