Notes:
First issue with boxed MC colophon on cover. Tied with Journey Into Mystery (Marvel, 1952 series) #69 (on sale date the same) as first use of MC brand, which is considered to be the first use of the company being called Marvel Comics in the 1960s.
On sale date from the publication date and volume number as reported to the U.S. Copyright Office found in the Catalog of Copyright Entries, Third Series, Volume 15, Part 2, Number 1, Periodicals, January-June 1961, page 116. Class B periodical. Copyright registration number B895315.