Macmillan, New York, 1948, 40^th pr.  ISBN 0-02-322410-X.  Trade soft cover, 70 pages.  Very good; faint creases on front wrap, crease at lower rear wrap corner; interior clean and unmarked; some foxing on outer page block.  Translated by F. J. Church; Translation revised, with an introduction, by Robert D. Cumming.  Part of the Library of Liberal Arts series.