What is the paper type that the one that was issued on 26 july 2007 done on?
CREATE TABLE "2007" (
  "date_of_issue" text,
  "denomination" text,
  "design" text,
  "paper_type" text,
  "first_day_cover_cancellation" text
);
SELECT "paper_type" FROM "2007" WHERE "date_of_issue"='26 july 2007';