UdG users
1949-03-22 Letter
1950-04-25 Letter
1950-09-12 Letter
1951-01-03 Letter
1951-09-17 Letter
1952-10-05 Letter
1952-12-22 Letter
1953-03-23 Letter
1953-06-14 Letter
1953-08-03 Letter
1953-08-19 Letter
1954-01-04 Letter
1954-03-10 Letter
1954-05-13 Letter
1954-11-22 Letter
1955-10-12 Letter
1961-05-31 Letter
1966-11-28 Letter
s.d. Letter