Hvid, Ivan, and Björn Strömqvist. “Proceedings of the Scandinavian Orthopedic Association 44th Assembly: Århus, Denmark, June 8–11, 1988”. Acta Orthopaedica, vol. 59, no. sup227, Jan. 1988, pp. 7-132, doi:10.3109/17453678809155633.