Silverberg used this title twice, in 1959 and 1961, for what are apparently distinct works. The 1959 version was also published as The Passion Barons.
Other resources
(None on file)
Acknowledgements: Robert Silverberg for cause, support, and cooperation; Ken Seamon for graphics; Rodney Walters for books and info; Alvaro Zinos-Amaro for comments and content; and all the fellow fans who have sent encouragement, information, and translations.