The list of members comprises currently 61 colleagues names from 28 countries. 50 members have stated their interest in active collaboration whilst 11 others are interested in receiving information on activities and results of the group. Unfortunately there are presently no active members from the United States or from the United Kingdom.
Proposals are welcome.
Altogether 17 countries are covered, with more than one from eight countries. Five answers also include detailed information on relevant literature and in ten others some relevant publications are listed. The efforts of all those who have replied so far are highly appreciated. Some first results are appended to this circular. Everyone, who has completed the questionnaire only partially and promised to give more detailed or more precise information at a later date, is asked to forward his supplements.