References in periodicals archive ?
Kirkwood was the director of environmental health for Calhoun County, Michigan, in the 1970s and went on to become the director of the department of environmental health for the state of Michigan from 1975 to 1997.
Vegetation associated with the Heisler Mastodon Site, Calhoun County, Michigan. Michigan Academician 19(1): 133-40.
In March 1997, a total of 153 cases of hepatitis A were reported in Calhoun County, Michigan (1990 population: 136,000); 151 case-patients have been students or staff of schools in four different school districts.