CREATE TABLE table_8711 ("Developer ( s ) " TEXT, "Release date" TEXT, "Required OS" TEXT, "Payment" TEXT, "Type" TEXT)

Which Release date has a Developer(s) of microsoft research?
SELECT "Release date" FROM table_8711 WHERE "Developer(s)" = 'microsoft research'
SELECT "Release date" FROM "table_8711" WHERE "Developer(s)" = 'microsoft research'