...and then after you have your library "clean" you may find that a couple of new additions run afoul of your desired pattern. When it's only an occasional author that needs fixing it is easier to use the Tag Browser by:
- Display the Tag Browser (use the View button in the lower right of the main window) and navigate to the particular author entry that needs fixing.
- Right-click (or Alt-click) on the entry that needs fixing and choose "Rename ..."
- Type the corrected name and then press Enter.
calibre will no merge the books using the old incorrect name with those using your "correct" form.