The Robot's RevengeBook - 1993
"The Hardy's invention, Roger the Lobber, an automatic tennis ball retrieval and return unit, has been stolen from the Teen Inventor's Club competition and then reappears without warning, transformed into a device of danger." -- Google Books
Publisher: New York City, New York : A Minstrel Book published by Pocket Books, a division of Simon & Schuster Inc., ©1993.
Characteristics: 151 pages ;,20 cm