00996nam--2200349---450-99000203307020331620040928113006.0000203307USA01000203307(ALEPH)000203307USA0100020330720040928d1971----km-y0itay0103----baengAT||||||||001yyNormative systemsCarlos E. Alchourron and Eugenio BulyginWien [etc.]Springer1971XVIII, 208 p.24 cm.Library of exact philosophy2001Library of exact philosophy2001001-------2001ALCHOURRON,Carlos E.348350BULYGIN,Eugenio54148ITsalbcISBD990002033070203316Collez. SW 55163 G.Collez. SWBKGIUSIAVPROV1020040928USA011130Normative systems1040283UNISA