• The title is given as ''Planet Explorer'' on the title page, but as ''The Planet Explorer'' on the cover and on the spine.
• "Complete and Unabridged" on the title page.
• No publication date explicitly stated, but the copyright date is given as 1957, one year after the original hardcover edition. Tuck and Currey concur.
• Tuck lists the catalog ID as "T202", but the ID on the cover and spine appears as "T-202".
• The artist is not credited; Sussman's shortened signature is on the cover (see some examples here).
• Printed in the US