Columbia Aniversity College of Physicians and Surgeons 630 WEST 168TH STREET NEW YORK 32, N. Y. DEPARTMENT OF BIOCHEMISTRY July 3, 1946 Dr. Joshus Lederberg Yale University Osborn Botanical Laboratory New Haven, Connecticut Dear Joshua: I found your letter of May 27th on my return to the laboratory. As soon as I get organized I propose to resolve the fluorophenylalanine. When vou are next in New York drop in to see me. Regards, pian fr