1. Garner, R. J. (1946). Grafters’ Handbook. Faber & Faber, London.
2. Grubb, N. H. (1949). Cherries. Crosby Lockwood & Son, Ltd., London.
3. Willison, R. S. (1950). Virus diseases of fruit trees. I. Some field observations on stone fruit in Southern England. Ann. Rep. Long Ashton Res. Sta. for 1949, 64.