 The Bayer letter ο (omicron) has been variously applied to two or three of the stars 30, 31, and 32 Cygni.30 Cygni has sometimes been designated as ο1 Cygni with the other two stars being ο2 and ο3 respectively.For clarity, it is preferred to use the Flamsteed designation 30 Cygni rather than one of the Bayer designations.