a nonfiction book on zenobia

In a comment below, Judith Weingarten, the author of  The Chronicle of Zenobia: The Rebel Queen, highly recommends this book:

Palmyra and Its Empire:  Zenobia's Revolt against Rome
by Richard Stoneman
University of Michigan Press
Reprint edition (March 15, 1995)

Richard Stoneman, a Senior Editor at Routledge, has published numerous books on the ancient world and on travel in the Eastern Mediterranean.  There is a long list at Amazon if you click on the author link in the above title.