Born-Digital or AnalogAnalogTranscriptManholes and manhole covers Sale of them is index of conditions. Post Ag 17,1949 P 3 2,000 manholes link city services. Post AP 14, 1958 P.20 Have become a $1 million a year business in Denver. Post Ja 26, 1970 P.1 Article describing notable manhole covers in California streets. California Historical Quarterly v.55 winter 1976 #4 P.353CollectionWestern History Subject IndexRelated MaterialWestern History Subject Index AbbreviationsType of MaterialIndex CardLanguageeng
Manholes and manhole covers, [404303]. Denver Public Library Digital Collections, accessed 19/05/2025, https://digital.denverlibrary.org/nodes/view/1785535
