Reverting References
The Revert Reference command undoes (reverts) all changes made to a reference since it was last opened or saved. Revert Reference is not available after you close the reference.
To revert changes, right-click in the Edit panel, then select Revert Reference from the list.
To remove the very last change made to a reference, use the Undo (Ctrl+Z) command in the Edit menu before leaving the field.