I don't have the Citations and Bib section under my Reference tab on the Ribbon. When I go to Customize Ribbon, I see in the big Main Tabs window under Customize the Ribbon on the right, and there's a checkmark by Reference. Citations and Bib shows up under Refs when I expand the plus sign; it should appear on the Ribbon but it's not there. What would make this happen and how can I get it onto the Ribbon under References?

Thank you.