Nachbar, F., Stolz, W., Volkenandt, M. and Meurer, M. (1993) “Squamous cell carcinoma in localized scleroderma following immunosuppressive therapy with azathioprine”., Acta Dermato-Venereologica, 73(3), pp. 217–219. doi: 10.2340/000155555573217219.