December 20, 1957
Dear Dr. Lederberg:
This is just to remind you of our conversation after the Harvey lecture.  I should be most interested in testing your DAP auxographs with regard to their biochemical block.  I would also be interested in your method of selection which was only briefly sketched out during your lecture.
Sincerely yours,
Charles Gilvarg
[HANDWRITTEN:] P.S. In case this may be of some interest to you I am sketching out what is known of DAP biogenisis so far.
[DIAGRAM AND SCIENTIFIC FORMULAS]