1. Cohen, A.S. and Calkins, E. Nature 183, 1202–1203, 1959.
2. Abrahams, C., Pirani, C.L. and Pollak, V.E. J. Pathol. Bacteriol. 92, 220–225, 1966.
3. Albores-Saavedra, J., Ròse, G.G., Ibanez, M.L. et al. Lab. Invest. 13, 77–93, 1964.
4. Bari, W.A., Pettengill, O.S. and Sorenson, G.D. Lab. Invest. 20, 234–242, 1969.
5. Battaglia, S. Klin. Wochenschr. 39, 795–798, 1961.