1. Piulachs, P.: Ulcers of the Legs, p. 11. Charles C Thomas, Springfield, Ill., 1956.
2. Leriche, R., AND Policard, A.: The Normal and Pathological Physiology of Bone: Its Problems, p. 188 ff. Authorized translation by S. MOORE AND J. A. KEY, C. V. Mosby Co., St. Louis, 1928.
3. Tracheopathia Osteoplastica
4. HETEROPLASTIC BONE FORMATION IN THE FALLOPIAN TUBE