00550nam a2200169ua 4500001000700000008004100007082001400048100002100062245004200083260004600125300001100171490001900182591002100201650002300222999001700245952011800262007293181020s1979    ck     gr     000   spa d04a503bS5481 aShepherd, Walter13aLa ciencia avanza / cWalter Shepherd  aBuenos Aires : bEditorial Losada, c1943  a541 p.0 aCiencia y vida  a7293 - Seminario14aCiencias básicas  c43280d43280  00104070aSEMINARIObSEMINARIOd2019-03-13l0o503 S548pBPSC010267r2019-03-13 00:00:00tEj. 1w2019-03-13yBK