CREATE TABLE table_19858 ("Stage" FLOAT, "Winner" TEXT, "General classification" TEXT, "Points classification" TEXT, "Mountains classification" TEXT, "Combination classification" TEXT, "Team classification" TEXT)

what is the minimum stage where mountains classification is aitor osa and aitor gonz lez won?
SELECT MIN("Stage") FROM table_19858 WHERE "Mountains classification" = 'Aitor Osa' AND "Winner" = 'Aitor González'
SELECT MIN("Stage") FROM "table_19858" WHERE "Mountains classification" = 'Aitor Osa' AND "Winner" = 'Aitor González'