UdG users
1958-01-20 Letter
1958-05-26 Letter
1958-11-15 Letter
1958-12-01 Letter
1959 Letter
1959-11-02 Letter
1960-01-28 Letter
1962-02-04 Letter
1965-04-05 Letter
1973-09-14 Letter
1976-10-07 Letter
1976-11-06 Letter
1976-11-15 Letter
1976-12-17 Letter
1977-07-05 Letter
1980-10-28 Letter
1980-11-01 Letter
1980-11-13 Letter
1980-12-24 Letter
1981-02-21 Letter
1981-10-13 Letter
1981-10-30 Letter
1981-11-20 Letter
1981-12-03 Letter