00503nam a2200181Ia 4500008004100000020001500041082001700056100001900073245003300092260004200125300000800167650001400175650002000189653003000209653002500239653003800264700001900302170901s1977    xx            000 0 und d  a0471995029  a333.76bD20C  aDavidson, Joan 0aConservation and Agriculture  aChichesterbJohn Wiley and Sonsc1977  a252  aEconomics  aSocial sciences  aAgricultural conservation  aAgricultural ecology  aConservation of natural resources  aLloyd, Richard