UdG users
1960-01-12 Letter
1960-12-27 Letter
1961-07-12 Letter
1961-07-22 Letter
1961-10-10 Letter
1961-11-10 Letter
1962-10-21 Letter
1962-12-22 Letter
1963-12-10 Letter
1964-06-12 Letter
1964-10-10 Letter
1965-01-19 Letter
1965-02-13 Letter
1965-02-20 Letter
1965-03-24 Letter
1965-05-12 Letter
1965-05-25 Letter
1965-06-08 Letter
1965-06-30 Letter
1965-07-30 Letter