1. Brinkley, B. R. & Stubblefield, E. Adv. Cell Biol. 1, 119–185 (1969).
2. Nicklas, B. R. Adv. Cell Biol. 2, 225–297 (1971).
3. Corces, V. G., Salas, J., Salas, M. L. & Avila, J. Eur. J. Biochem. (in the press).
4. Corces, V. G. & Avila, J. Eur. J. Biochem. (in the press).
5. Conolly, J. A., Kalnins, V. I., Cleveland, D. W. & Kirschner, M. W. Proc. natn. Acad. Sci. U.S.A. 74, 2437–2440 (1977).