00254nam a2200109Ia 4500082001800000100001900018245003900037260004300076300001500119500000500134700000500139  a382.7bJ67.AT  aJohnson, H. G.  aAspects of the theory of tariffsb  aLondonbGeorge Allen & Unwin Ltdc1971  axii, 451p.  a  a