1. Flint A: A Treatise on the Principles and Practice of Medicine, 5th ed. Henry C. Lea’s Son, Philadelphia, 1881, p. 205.
2. Flint A: A Treatise on the Principles and Practice of Medicine, 5th ed. Henry C. Lea’s Son, Philadelphia, 1881, p. 208.
3. Koch R: The aetiology of tuberculosis. Berliner Klin Wochenschr 19: 221, 1882; National Tuberculosis Association, New York (translated by Dr and Mrs M Pinner), 1932.
4. Koch R: The aetiology of tuberculosis. Berliner Klin Wochenschr 19: 221, 1882; National Tuberculosis Association, New York, 1932 (translated by Dr and Mrs M Pinner), p. 31.
5. Flint A: A Treatise on the Principles and Practice of Medicine, 6th ed. Henry C. Lea’s Son, Philadelphia, 1886, pp. 194–195.