1. Rasmussen, H., Science, 170, 404 (1970).
2. Pannbacker, R. G., Fleishman, D. E., and Reed, D. W., Science, 175, 757 (1972).
3. Price, S., in Olfaction and Taste (edit. by Schneider, D.), 4 (Springer-Verlag, Berlin, in the press).
4. Dastoli, F. R., and Price, S., Science, 154, 905 (1966).
5. Price, S., and Hogan, R. M., in Olfaction and Taste (edit. by Pfaffmann, C.), 3, 397 (Rockefeller University Press, New York, 1969).