in Marvel Special (Marvel Italia, 1994 series) #6 (Aprile 1996)
in The X-Men Omnibus (Marvel, 2009 series) #1 ([April] 2009), #1 ([April] 2009)
in The X-Men (Marvel, 1963 series) #68 (February 1971)
in Marvel Masterworks: The X-Men (Marvel, 2003 series) #7 [Regular Edition] ([October] 2008)
in Essential Classic X-Men (Marvel, 2006 series) #3 [black & white]
in The Official Marvel Index to the X-Men (Marvel, 1987 series) #1 (May 1987)
in Marvel Masterworks (Marvel, 1987 series) #7 ([Novenber] 1988)
in X-Men: The Early Years (Marvel, 1994 series) #15 (July 1995)
in Essential Uncanny X-Men (Marvel, 1999 series) #1 (September 1999)
in The X-Men Omnibus (Marvel, 2009 series) #1 ([April] 2009)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).
in The X-Men (Marvel, 1963 series) #68 (February 1971)
in Marvel Masterworks (Marvel, 1987 series) #7 ([Novenber] 1988)
in X-Men: The Early Years (Marvel, 1994 series) #15 (July 1995)
in Marvel Special (Marvel Italia, 1994 series) #6 (Aprile 1996)
in Essential Uncanny X-Men (Marvel, 1999 series) #1 (September 1999)
in The X-Men Omnibus (Marvel, 2009 series) #1 ([April] 2009)Story continued in X-Men 16