00277nam a2200109Ia 450000500170000000800410001708200160005810000160007424500340009026000350012430000080015920260225051113.0260224s9999||||xx |||||||||||||| ||und||  a631.522 MAY  aOliver Mayo 4aThe theory of plant breeding   aOxford: Clarendon Press c1987  a334