Mumford, Lewis. (1895–1990) "Until this work is done I cannot engage to go anywhere." - Autograph Letter SignedALS from the American historian to Professor Irma Antonetto of the Associazione Culturale Italiana, declining an invitation to speak. 14th March 1964; 1 pp., on personal stationary. "Dear Professor Antonetto I am grateful to the Associazione Culturale Italiana for the invitation to lecture in Italy next winter. It would give me great pleasure to do so; but the book I am now working on may not be finished before next April: and until this work is done