2) Hay, R. J., Mackenzie, D. W. R., Campbell, C. K. and Philpot, C. M.: Cryptococcosis in the United Kingdom and the Irish Republic: an analysis of 69 cases. J. Infect., 2: 13-22, 1980.
3) Emmons, C. W.: Saprophytic sources of Cryptococcus neoformans associated with the pigeon (Columba livia). Am. J. Hyg., 62: 227-232, 1955.
4) Partridge, B. M. and Winner, H. I.: Cryptococcus neoformans in bird droppings in London. Lancet, i: 1060-1061, 1965.