UdG users
1955-11-25 Letter
1956-08-17 Letter
1957-08-26 Letter
1957-12-11 Letter
1958-02-08 Letter
1958-02-12 Letter
1958-05-05 Letter
1958-06-06 Letter
1958-06-10 Letter
1958-07-07 Letter
1958-08-09 Letter
1958-10-21 Letter
1959-04-19 Letter
1959-07-03 Letter
1959-09-21 Letter
1959-12-03 Letter
1960-06-07 Letter
1960-10-01 Letter
1960-12-09 Letter
1961-04-24 Letter
1961-07-06 Letter