Dr. Holló Ferenc szerk.: Parasitologia Hungarica 3. (Budapest, 1970)

LUDLAM, G.B.: Toxoplasma Antibodies in Inhabitants of the Niger Delta. - Trans. Roy. Soc. Trop. Med. Hyg.

, 59, 83-86, 1965MacMAHON, B. et al

.: Epidemiologic Methods. Little, Brown and Company, Boston, Toronto, I960. MURAKAMI, P.: Epidemiological Studies on Toxoplasmosis. I. Prevalence of Toxoplasma Antibodies in Residents in Nagasaki Prefectura,including Pregnant Women,Slaughter House Workers, Butchers,Veterinarians and Dog-Catchers. - Endem. Dis. Bull. Nagasaki Univ., 6, 1-12, 1964. ROBERTSON, I.S.: Excessive Perinatal Mortality in a Small Town associated with Evidence of Toxoplasmosis. - Brit. Med. J., 9, 91-96, I960. WALLS

, K.W. - KAGAN, I.K.: Studies on the Prevalence of Antibodies to Toxoplasma gondii. 2.Brazil. - Am.J.Jour. Epid., 86, 305-313, 1967. WALTON, B.C. et al

.: Relationship of Toxoplasma Antibodies to Altitude. - Am. J. Trop. Med. Hyg., 15, 492-495, 1966. WESTPHAL, A. - BAUER, P.: Weitere Untersuchungen und Betrachtungen zur Toxoplasmose-Komplementbindungsreaktionnach Westphal. - Z. Tropenmed. Parasit., 3, 326-339, 1952. The WHO Standard Tuberculin Test. - WHO Techn. Rep. 3. Geneva, 1963. Received: 12.5-1970. Dr. MÁRIA JANKÓ Dr. ENDRE CZEIZEL Department of Parasitology

,Nationale Institute for Public Health, Budapest, IX. Gyáli-ut 4.