Letter on a Form The chairman of WG 2.1 reportes on the meeting of WG 2.1 which took place at the University of Oxford on 1977, December 16 to 22. Agenda Item 6.0 of 23rd Meeting of TC-2. Date: 10.01.1978 Original document language: English Authors: John E. L. Peck Addressee: Manfred Paul