I found my Zirbel's in Iowa. My records are packed right now, just moved, so I am not sure if there is a Charlie Zirbel in the line. At one time I thought they were in Wisconsin but another researcher set me straight.
Does your book discuss Zirbel's in Iowa, mine are mainly in Cerro Gordo and Hancock Counties?
Thanks for taking the time to respond to my query. Any assistance is appreciated. :)