1. Alm, I.: Acta paediat. (Uppsala) Suppl.94 (1953).
2. Ammich, O.: Virchows Arch. path. Anat.302, 539 (1938).
3. Apple, C.: Amer. J. Ophthal.37, 68 (1954).
4. Arajärvi, T.: Microscopic investigations into the capillaries of newborn, especially premature infants, taking into account the sensitivity of capillaries to adrenalin and their intravascular red cell aggregation. Thesis, Helsinki, 1953.
5. Ashton, N.: Amer. J. Ophthal.39, No 4, Part II, 153 (1955).