1. Abdullah R, Cocking EC, Thompson JA (1986) Bio/Technology 4: 1087?1090.
2. Arnold S von, Eriksson T (1976) Physiol Plant 36: 193?196.
3. Chen WH (1978) M Phil Thesis, Univ of Leicester, UK.
4. Chen WH, Davey MR, Power JB, Cocking EC (1988) J Exp Bot 39: 251?261.
5. Chen WH, Gartland KMA, Davey MR, Sotak R, Gartland JS, Mulligan BJ, Power JB, Cocking EC (1987) Plant Cell Rep 6: 299?301.