> as lemmas

1949 W. Feller First Berkeley Symp. Math. Statistics & Probability 418 What ergodicity might possibly mean in practice may be illustrated by the much discussed Pareto law of income distribution.

1960 G. Herdan Type-token Math. xx. 296 Under certain circumstances a system will tend in probability to a limiting form which is independent of the initial position from which it started. This is the Ergodicity Property.