The comic is an adaptation of the 1844 novel "Les Trois Mousquetaires [The Three Musketeers]," by Alexandre Dumas, père.
The indicia states the title is Marvel Classics Comics Featuring The Three Musketeers.
The title page includes the credit "A Vincent Fago Production."
This issue is a variant of
Marvel Classics Comics (Marvel, 1976 series) #12 - The Three Musketeers.