1. Acheson, G. H.: Physiology of neuro-muscular junctions: chemical aspects. Fed. Proc.7, 447–457 (1948).
2. Adrian, E. D.: Some recent work on inhibition. Brain47, 399–416 (1924).
3. —, andD. W. Bronk: The discharge of impulses in motor nerve fibres. Part II. The frequency of discharge in reflex and voluntary contractions. J. Physiol. (Lond.)67, 119–151 (1929).
4. Adrian, R. H.: Potassium chloride movement and the membrane potential of frog muscle. J. Physiol. (Lond.)151, 154–185 (1960).
5. Aitken J. T., andJ. E. Bridger. Neuron size and neuron population density in the lumbosacral region of the cat's spinal cord. J. Anat. (Lond.)95, 38–53 (1961).