The British War Blue Book, Miscellaneous No. 9 (1939). Documents Concerning German-Polish Relations and the Outbreak of Hostilities Between Great Britain and Germany on September 3, 1939. Presented by the Secretary of State for Foreign Affairs to Parliament by Command of His Majesty. London: Government of the United Kingdom, 1939. Web, Avalon Project.
The French Yellow Book. 1939. Web, Avalon Project.
Lipski, Józef, and Wacław Jẹdrzejewicz. Diplomat in Berlin, 1933-1939; papers and memoirs of Józef Lipski, Ambassador of Poland. New York: Columbia University Press, 1968. Print. Available at Archive.org.