UdG users
1980-04-30 Letter
1980-05-13 Letter
1980-05-19 Letter
1980-06-02 Letter
1980-08-26 Letter
1981-07-31 Letter
1981-10-24 Letter
1981-11-16 Letter
1981-11-22 Letter
1982-10-20 Letter
1985-02-18 Letter
1985-02-24 Letter