OK, so it looks like there actually was a Fourth Provincial Council held in Milan in 1576. Eleven bishops were present: https://archive.org/details/amanualofcou

OK, so it looks like there actually was a Fourth Provincial Council held in Milan in 1576. Eleven bishops were present: https://archive.org/details/amanualofcouncil01landuoft https://archive.org/details/amanualofcouncil01landuoft - although I'm not sure how binding the decisions of this Council are (if you live in Rome, are you excommunicated, too?). The references lead to Richard Trexler's article "Infanticide in Florence" in Dependence in Context in Renaissance Florence which is out of print.