00319    a2200133   450000500170000004100080001708200100002510000260003524500320006126000430009330000080013665000180014465000230016220260521114632.001aENG01a551.401aThornbury, William D.01aPrinciples of geomorphology01aNew DelhibWiley Eastern Limitedc196901a59401aGeomorphology01aPhysical geography