HM-01-04 1877 Geologic Map of Colorado (Hayden) (detail) HM-01A Six 1877 Geologic Map Sheets and Two Cross Sections of Colorado (Hayden)
HM-01-16 1877 Geologic Map HM-01-16 1877 Geologic Map, Sheet XVI: South-Central CO and Part of NM (Hayden)
HM-01-15 1877 Geologic Map HM-01-15 1877 Geologic Map, Sheet XV: SW CO and parts of NM, AZ and UT (Hayden)