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by Fradin, Dennis B.
by Lampton, Christopher
by Heath-Stubbs, John Francis Alexander
by Huber, Peter W
by Chaple, Glenn F.
by Sipiera, Diane M.
by Edited by Mario Livio , Stefano Casertano
by Michael A. Covington
by Edited by Mario Livio , Keith Noll , Massimo Stiavelli
by Guy Consolmagno , Dan M. Davis