00272nam a2200121Ia 4500020001400000082002200014100002000036245004300056260002800099300001300127500000500140700000500145  a333169166  a338.528bA1428.IN  aAllen, R. G. D.  aIndex numbers in theory and practicsb  aLondonbMacmillanc1975  ax, 278p.  a  a