Denver and Rio Grande Railroad Freight Train Climbing Grade to Cumbres Pass. Colorado (SE-RG-160)
MLA
Plowden, David. Denver and Rio Grande Railroad Freight Train Climbing Grade to Cumbres Pass. Colorado (SE-RG-160). 1962. https://collections.library.yale.edu/catalog/2041707.
APA, 6th edition
Plowden, D. (1962). Denver and Rio Grande Railroad Freight Train Climbing Grade to Cumbres Pass. Colorado (SE-RG-160). https://collections.library.yale.edu/catalog/2041707.