Hansen, Hans-Jörgen. “A Pathologic-Anatomical Study on Disc Degeneration in Dog: With Special Reference to the So-Called Enchondrosis Intervertebralis”. Acta Orthopaedica, vol. 23, no. sup11, Dec. 1952, pp. 1-130, doi:10.3109/ort.1952.23.suppl-11.01.