Anna M. Cienciala, «Poland in British and French Policy in 1939: Determination to Fight — or Avoid War?», Polish Review, 34 (1989), 199-226; Watt, How War Came, 162-87; Parker, Chamberlain and Appeasement, 204-6; Simon Newman, March 1939: The British Guarantee to Poland: A Study in the Continuity of British Foreign Policy (Oxford, 1976); Philip M. H. Bell, The Origins of the Second World War in Europe (London, 1986), 250-55.