Read this excerpt from the references page of The Riddle of the Rosetta Stone. Andrews, Carol. The British Museum Book of the Rosetta Stone. New York: Peter Bedrick Books, 1985.
Budge, Sir E. A. Wallis. The Rosetta Stone in the British Museum. London: The Religious Tract Society, 1929.

–The Riddle of the Rosetta Stone,
James Cross Giblin
HURR
What conclusion can be drawn from the excerpt?

The books listed provided the author with illustrations.
The Riddle of the Rosetta Stone was published after 1985.
These were the two reference works the author found most useful.
The author obtained the same information from both of the books listed.