CREATE TABLE table_21105 ("Story #" FLOAT, "Title" TEXT, "Doctor" TEXT, "Narrator" TEXT, "Format" TEXT, "release date" TEXT, "Notes" TEXT)

What is the release date of the bonus interview with Peter Purves?
SELECT "release date" FROM table_21105 WHERE "Notes" = 'Bonus interview with Peter Purves'
SELECT "release date" FROM "table_21105" WHERE "Notes" = 'Bonus interview with Peter Purves'