Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_19858 ( "Stage" real, "Winner" text, "General classification" text, "Points classification" text, "Mountains classification" text, "Combination classification" text, "Team classification" text )

### Question ###
what is the minimum stage where mountains classification is aitor osa and aitor gonz lez won?

### Accurate SQL ###

SELECT MIN("Stage") FROM table_19858 WHERE "Mountains classification" = 'Aitor Osa' AND "Winner" = 'Aitor González'