John Lawson wrote on Thu, Jul 9, 2009 12:07 AM EDT:
I became a chess variantist in 1962, so yes I know how hard information was to find in the olden days.
Bob Abbott published a paperback book 'Abbott's New Card Games', Funk and Wagnalls, $0.95, in 1963, containing the rules to Ultima, so the possibility of cross-fertilization is there. I happen to have two copies.
But does it matter really? I see no reason to be concerned with 'primacy'. They are different games, inspired by an idea that could occur to anyone.