author display fields

Ver X4 Win XP. How do I show more than 1 author in the author display flield? (see attachment) Inserting secondary and tertiery author fields gives me nothing

Select the “Display all authors in the Author field” option which is located by going to the toolbar and selecting: EDIT, PREFERENCES, DISPLAY FIELDS (see image). 

DisplayAllAuthors.gif
DisplayAllAuthors.gif

Thanks. Iknew it was somewhere but it was too obvious