1. The Anatomy of the Bronchial Tree;Brock, R.C.,1954
2. Davies, C. N. (1949). Brit. J. industr. Med., 6, 245.
3. English translation by;Fischer, F.K.,1953
4. Hayward, J., and Reid, L. McA. (1952). Thorax, 7, 89.
5. Bronchography;Huizinga, E.; Smelt, G.J.,1949