Note that the index numbers are only technical numbers which have no persistence. After a new system generation is done, all of them are invalid. To generate a persistent link, use the name.Use the URL:
http://ww-person.com/cgi-bin/l3/LANG=germ/F=Jean/N=de@Longchamp@*@de@Longchamps@et@du@Sart@*@d'Upigny
Jean de Longchamp * de Longchamps et du Sart * d'Upigny
alternatively: /cgi-bin/llmult/LANG=germ/P=14001001