1. Read, P.E. (1990) in Handbook of Plant Cell Culture (Ammirato, P.V., Evans, D.A., Sharp, W.R. and Bajaj, Y.P.S. eds.), Vol. 5, pp. 95–125, McGraw Hill, New York
2. Evans, D.A. and Bravo, J. E. (1986) in Tissue Culture as a Plant Production System for Horticultural Crops (Zimmerman, R.H., Griesbach, R.J., Hammerschlag, F.A. and Lawson, R.H., eds.), pp. 73–96, Matinus Nijhoff, Dordrecht
3. Preil, W. (1986) in Genetic Manipulation in Plant Breeding (Horn, W., Jensen, C.J., Odenbach, W. and Schieder, O., eds.), pp. 377–403, Walter de Gruyter & Co., Berlin
4. Chu, I.Y.E. and Kurtz, S.L. (1990) in Handbook of Plant Cell Culture (Ammirato et al., eds.), Vol 5, pp. 126–164, McGraw Hill, New York
5. Constantine, D.R. (1986) in Plant Tissue Culture and Its Agricultural Applications (Withers, L.A. and Alderson, P.G., eds), pp. 175–186, Butterworths, London