You can use the Math Department Internal email List Groups to send an email to a select group or groups of people.
Click here for the organizational chart: https://drive.google.com/file/d/0B40e9Z9kAtceM2RVbE93Y3NjZ3c/view
To view the members of each group you may visit: https://groups.google.com
Click the blue "Browse All" button.
Click on a group (eg. fac-emeritus) and then click "Members" near the top right corner of the page to browse all members.
Contact firstname.lastname@example.org If you receive an error or do not have access to view a list.