CREATE TABLE table_15059783_1 (mountains_classification VARCHAR, winner VARCHAR, points_classification VARCHAR)

If winner is alejandro Valverde and the points Classification is by Erik Zabel, who is the mountain classification?
SELECT mountains_classification FROM table_15059783_1 WHERE winner = "Alejandro Valverde" AND points_classification = "Erik Zabel"
SELECT "mountains_classification" FROM "table_15059783_1" WHERE "Alejandro Valverde" = "winner" AND "Erik Zabel" = "points_classification"