UdG users
1966-02-10 Letter
1966-03-14 Letter
1967-05-11 Letter
1967-12-07 Letter
1969-06-21 Letter
1969-08-05 Letter
1970-02-13 Letter
1970-04-17 Letter
1975-09-17 Letter
1975-10-24 Letter
1977-01-21 Letter
1977-02-18 Letter