Originally an opt-in Wikipedia Gadget, Reftoolbar was moved to a site-wide script on February 25, 2011, and to an opt-out gadget on April 2014. It comes in two versions, depending on the settings at Preferences → Editing → Editor.
The default for all users, logged in or not, is refToolbar 2.0.
Click on the version number for more information about each refToolbar implementation.
Cite icon on right
Cite menu item on right
The RefToolbar style column indicates the widget that activates the cite mechanism.
Before 2017, there were three versions of Refoolbar: 1.0, 2.0a and 2.0b. Version 2.0a was removed on June 14, 2017, since it was no longer needed.
If your toolbar looks like this:
If you want to learn how to use that Cite menu, please refer to the Visual Editor user guide.
This image file is found at commons:File:Wikipedia reftoolbar dependency graph.svg.