Help:Introduction to referencing with VisualEditor/3
Why references are important
Automatically or manually
Some are just really useful
Which sources are good enough?
Review of what you've learned
To edit an existing reference, click on the [number] where it appears in the text. You will see either a icon, or the icon (and name) for the template that was used to create this reference. Clicking on this icon will open a "template mini-editor" dialog where you can edit the information for that reference.
Inside the template mini-editor, you change the information in fields by typing in the boxes.
To add a new piece of information (for example, the publication date), click on "Edit", which is at the very bottom of the mini-editor.
When you're done editing the reference, click "Apply changes". Remember, you'll still need to then save your changes!