1. G. Zlokarnik, P. A. Negulescu, T. E. Knapp, L. Mere, N. Burres, L. Feng, M. Whitney, Aurora Biosciences, 11010 Torreyana Road, San Diego, CA 92121, USA.
2. K. Roemer, University of the Saarland, D-66421 Homburg/Saar, Germany.
3. R. Y. Tsien, Howard Hughes Medical Institute and Department of Pharmacology, University of California at San Diego, La Jolla, CA 92093–0647, USA.