What is the mountain classification of Mario Cipollini, who has a general classification of Pavel tonkov?
CREATE TABLE "classification_leadership_by_stage" (
  "stage" text,
  "winner" text,
  "general_classification" text,
  "points_classification" text,
  "mountains_classification" text,
  "intergiro_classification" text,
  "trofeo_fast_team" text
);
SELECT "mountains_classification" FROM "classification_leadership_by_stage" WHERE "winner"='mario cipollini' AND "general_classification"='pavel tonkov';