4) I. Tasaki, A. Watanabe, R. Sandrin & L. Carnay: Changes in fluorescence, turbidity, and birefringence associated with nerve excitation, Proc. Nat. Acad. Soc. USA., 61, 883/888 (1968)
5) L. B. Cohen, R. D. Keynes & D. Landowne: Changes in axon light scattering that accompany the action potential in squid giant axons: potential-dependent components, J. Physiol. (Lond.), 224, 701/725 (1972)