Continued in X-MEN (Marvel, 1963 series) #94. This series is broken into four parts, Second Genesis (13 pages), Chapter II ...And When There Was One! (7 pages), Chapter III Assault Force (8 pages), and Chapter IV Krakoa... the Island That Walks Like a Man! (8 pages).
Sources for particularization of story/script credits are The Marvel Comics Index (Olshevsky 1981) and The Official Marvel Index to the X-Men (Olshevsky 1987).
Peter Iro is credited with background inks in many sources, but none of his work was in the finished product, per Dave Cockrum: "First--your listing of X-Men Special Edition #1 lists Peter Iro as one of the creative team on Giant-Size X-Men #1. It's about time somebody put the lie to this one: Pete Iro did indeed try his hand at inking my backgrounds on FIVE PAGES ONLY. [Emphasis his] Even if a background assistant completes a full job, he gets no credit whatsoever for having worked on the job. But aside from that, the five pages he inked were so crudely and amateurishly butchered that I was forced to white out all his work and re-ink those pages myself. In view of this fact, it's obvious why I resent Iro being listed as having worked on the book: I inked that book entirely, and no one else." (The Comic Reader #208)
Marvel Girl featurette
Edited reprint: a caption on page 1 is rewritten, and page 2 is cut.