from The X-Men (Marvel, 1963 series) #42 (March 1968)
in Marvel Special (Marvel Italia, 1994 series) #15 (Dicembre 1998)Sources for letters credits 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). Cover is taken from an unaltered stat, per Nick Caputo, June 2012.
from The X-Men (Marvel, 1963 series) #42 (March 1968)
from Amazing Adult Fantasy (Marvel, 1961 series) #7 (December 1961)