H. Zachariae, L. Halkier-Sørensen, P. Bjerring, and L. Heickendorff, “Treatment of ischaemic digital ulcers and prevention of gangrene with intravenous iloprost in systemic sclerosis”., Acta Derm Venereol, vol. 76, no. 3, pp. 236–238, May 1996.