Chris Claremont, Paul Smith
George Papp, Robert Bernstein
The Uncanny X-Men #169 - Catacombs
"Adventure Comics #283 (April, 1961)"
The Xavier Institute, Salem Center, Westchester County, New York State, (former) The Alley (beneath Manhattans surface), X-Factor Is sentient starship
Formerly Krypton; formerly the Phantom Zone; currently Earth