004280000a22001450004500060000800000082001700008100002300025100001500048100001100063245008700074260003500161260000900196300000800205650006900213  a100  a519.50 2 CHA  aChakravarthi, I.M.  aLaha, R.G.  aRoy, J  aHand book of methods of applied statistics V.2 planning of surveys and experimetns  aNewYork, John Wiley & Sons INC  c1967  a160  aApplied statistics/ sample selection/ sample survey - estimation