What is the date of the British Rail class 111 tslrb description?
CREATE TABLE "list_of_great_central_railway_locomotive" (
  "number_name" text,
  "description" text,
  "livery" text,
  "owner_s" text,
  "date" text
);
SELECT "date" FROM "list_of_great_central_railway_locomotive" WHERE "description"='british rail class 111 tslrb';