I've just traced this ancestor to Denver and can't find any obits for this time period online. Can anyone help on either of these?

Wallis Melvin Reef, died 3 June 1977 (worked for the state and seemed to be well known so I assume there would be an obit

Ruth Marie Graff Reef, buried 13 August 1923 (so assume she died just prior). She had just married Wallis Reef 10 months prior so possibly died in childbirth (just assumption)

Any help greatly appreciated!