William Blackstone, St. George Tucker (1996). “Blackstone's Commentaries: With Notes of Reference to the Constitution and Laws, of the Federal Government of the United States, and of the Commonwealth of Virginia: With an Appendix to Each Volume, Containing Short Tracts Upon Such Subjects as Appeared Necessary to Form a Connecte”, p.300, The Lawbook Exchange, Ltd.
Molotov's report on (29 March 1940), after the Polish defeat, as quoted in the weekly Soviet newspaper "Moscow News", published by Mezhdunarodnaya Kniga, April 1, 1940.