1. Attree SM, Fowke LC (1993) Embryogeny of gymnosperms: advances in synthetic seed technology of conifers. Plant Cell Tissue Organ Cult 35: 1–35
2. Bridgen MP, Bartok JW (1987) Designing a plant micropropagation laboratory. Comb Proc Int Plant Prop Soc 37: 462–467
3. Engelmann F (1994) Cryopreservation for the long–term conservation of tropical crops of commercial importance. In: Proc Int Symp Application of Plant in Vitro Technology. Serdang, Malaysia. Engelmann, France, FAX 33–67–547–800
4. Evans DA, Sharp WR, Amirato PV, Yamada Y (1983) Handbook of plant cell culture, vol 1. Macmillan, New York
5. Kartha KK (ed) (1985) Cryopreservation of plant cells and organs. CRC Press, Boca Raton, FL Kyle L (1987) Plants from test tubes. An introduction to micropropagation. Timber Press, Portland, OR