This issue has variants.
Pencil credits from Rich Donnelly via the GCD Errors List.
Sources for letters credit are The Marvel Comics Index (Olshevsky 1981), The Official Marvel Index to the X-Men (Olshevsky 1987), The Official Marvel Index to the X-Men (Ward 1994), and Official Index to the Marvel Universe (Vandal et al. 2009).
Continued in X-Men 23.
Letters from Walter Willis III, Walt Smith, Dean Crawford, Don Feese, A. George Resciniti, Dexter Musgrove, Christine Cassello, Jim Eastabrook, Francisco Cayse; M.M.M.S. entry form; "Next Ish" text.