What is the Stage when the points classification is Danilo Di Luca, Mountains classification is José Rujano, and general classification is Danilo Di Luca?
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,
  "trofeo_super_team" text
);
SELECT "stage" FROM "classification_leadership_by_stage" WHERE "points_classification"='danilo di luca' AND "mountains_classification"='josé rujano' AND "general_classification"='danilo di luca';