R. O. Niskanen, M. Y. Lehtimäki, M. M. J. Hämäläinen, P. Törmälä, and P. U. Rokkanen, “Arthrodesis of the first metatarsophalangeal joint in rheumatoid arthritis: Biodegradable rods and Kirschner-wires in 39 cases”, ActaO, vol. 64, no. 1, pp. 100–102, Jan. 1993.