00310cam a2200121ua 4500041001000000082001900010100001900029245006800048250001200116260004300128300001200171504000500183  aengh  a631.53bALL/PR  aAllard, R W  .  aPrinciples of plant breeding / cR W Allard.hTextual Documents  a1 / b.  aLondon : bJohn Wiley & Sons , c1960.  a484 ; .  a