
On the Ergodic Behavior of Dynamical Systems (LA-2055, May 10, 1955) in [Stanisław Marcin Ulam, Analogies between Analogies, The Mathematical Reports of S.M. Ulam and His Los Alamos Collaborators, University of California Press, 1990, http://ark.cdlib.org/ark:/13030/ft9g50091s/]