1. (Asimov's Pebble in the Sky) Memorandum of Agreement , 17 March 1969, between Sidgwick and Jackson and Sphere Books, four pages, folio, signed by Anthony Cheetham [Wikipedia] for Sphere Books. ?300 advance with percentages.2. (Asimov's Pebble in the Sky) Memorandum of Agreement between Doubleday & Company and Sidgwick & Jackson, 21 September 1967, three pages, folio, sl. crumpled, signed by Nelson Doubleday. It concludes with statement about copyright (Asimoc, 1950.
