Quote of Mondrian in a letter to Van Doesburg, 4 Dec. 1927; as cited in De Stijl 1917-1931 - The Dutch Contribution to Modern Art, by H.L.C. Jaffé http://www.dbnl.org/tekst/jaff001stij01_01/jaff001stij01_01.pdf; J.M. Meulenhoff, Amsterdam 1956, p. 27 <br class="br">Mondrian's answer to Theo van Doesburg's retrospective article in 'De Stijl' magazine in 1929, where he wrote: 'By the lively and most articulate evolution the principles, developed mainly by P. Mondriaan in 'De Stijl' could not any longer be considered as generally characteristic of the opinion of the group.' <br class="br">1920's