DESIGNED BY JOSEF HOFFMANN, MANUFACTURED BY J. & J. KOHN, CIRCA 1908

Chairs to this design were exhibited by J. & J. Kohn at the Kunstschau, Vienna, 1908 (see reproduction below); Hoffmann also used this design in the nursery at the Palais Stoclet.
Cf: Moderne Bauformen, 1908, pp. 371-5, (reproduced).
See also: Die Kunst, Vol. 18, 1908, pp. 53-59.