Question: William Richert served as acting mayor of Detroit, Michigan, after what four-term Republican mayor resigned?
Sentence (from "William Richert (mayor)"): William Richert (October 28, 1858 – June 16, 1912) served as acting mayor of Detroit, Michigan from March 22, 1897 to April 5, 1897, following the resignation of Hazen S. Pingree.
Relevant evidence: Yes