INSTITUTIONEN FOR CELLFORSKNING MEDICINSKA NOBELINSTITUTET KAROLINSKA INSTITUTET Stockholm, February 7. 1961. STOCKHOLM 60 Telefon 23 54 80 INSTITUTE FOR CELL RESEARCH KAROLINSKA INSTITUTET STOCKHOLM 60 Professor Joshua Lederberg Department of Genetics c:o Dr. George Derbyshire Stanford University Space Science Board Palo Alto, California, USA National Academy of Sciences 2101 Constitution Avenue Washington 25, D.C.USA Dear Professor Lederberg: Many thanks for your letter of January 23. I trust that you got my cable saying that I will be in Stanford from Monday night (February 13.) and stay to the end of the week. Any time suitable to you suits me well so please do not make undue hurry in Washington, I will fly directly from Stockholm to Los Angeles and take my Washington time after San Francisco so we will not meet in Washington, Looking forward to meeting you and Mrs. Lederberg soon, I am with best regards, Yours truly QW obs. Comper, Torbjérn Caspersson TC:dn