830 PARK AVENUE NEW YORK 21. NEW YORK March 15, 1949 Dr. Ludwig von Mises, 777 West End Avenue, New York 25, N.Y. Dear Dr. von Mises, As you probably know, Dr. Hahn is at present in Europe, and I am therefore acknowledging your letter of March 12th on his behalf. I am advising Dr. Hahn of the contents of your letter and, in the meantime, I know he would want me to thank you for your comments on "Economics of Illusion", which will be most useful in publicizing the book. Yours sincerely, G Sunclear