What is the Elector with a Nationality with roman, and an Elevator of urban iv, and an Elevated with 1261, december 17?
CREATE TABLE "cardinal_electors" (
  "elector" text,
  "nationality" text,
  "faction" text,
  "order_and_title" text,
  "elevated" text,
  "elevator" text
);
SELECT "elector" FROM "cardinal_electors" WHERE "nationality"='roman' AND "elevator"='urban iv' AND "elevated"='1261, december 17';