CREATE TABLE table_19127 ("Country or territory with flag" TEXT, "Area  ( km\\u00b2 )   ( per sqmi ) " TEXT, "Population  ( July 2009 est. ) " FLOAT, "Population density per km\\u00b2" TEXT, "Capital" TEXT)

What country's capital is buenos aires?
SELECT "Country or territory with flag" FROM table_19127 WHERE "Capital" = 'Buenos Aires'
SELECT "Country or territory with flag" FROM "table_19127" WHERE "Capital" = 'Buenos Aires'