1. Prerovskly I. Diseases of the veins. World Health Organisation, Internal comunication. Mho-Pa 10964.
2. Widmer LK. Perpheral venous disorders. Prevalence and social-medical importance. Observations in 4529 apparently healthy persons. Basel III Study. Bern Hans Huber, 1978.
3. Bartolo M, Di Fortunato T, Antigniani PL. Epidemiologia delle flebopatie. Min Ang 1989; 14:3–14.
4. Allegra C. Appunti di flebologia. Arti Grafiche Istaco, 1990:10–11.
5. Thompson H. The surgical anatomy of the superficial and perforating veins of the lower limb. Ann R Coll Surg Engl 1979:61–198.