contributions from Eckehard V. Dehmlow ... [et al.]. contributions from Kohlschutter ...[et al.]. contributions from Schlosser...[et al.]. contributions by H. Bilz ... [et al.]. contributions by J. C. Boeyens ...[et al.]. contributions by L. A. Anderson...[et al.]. contributions from A. Eide ... [et al.] ; reports from APRI ... [et al.]. [contributing writers: Burton Beers ... et al.] contributed by E. T. G. Emery ... [et al.]. contributing editors, D. Hui ... [et al.].