1. Algebraic surfaces, ed.I.R.Shafarevich. Proc.Steklov Math.Inst., vol.75, 1965(Engl.transit AMS,1967).
2. Artin M., On Enriques' surface. Harvard thesis,1960.
3. Beauville A., A letter to the author of September 25,1977.
4. Bombieri E., Canonical models of surfaces of general type,Publ.Math.I.H.E.S., 42(1973), 171–219.
5. 5 ——, Catanese F., A non-published manuscript.