Oswin Aichholzer Lyuba Alboul Ferran Hurtado On Flips in Polyhedral Surfaces. 303-311 2002 13 Int. J. Found. Comput. Sci. 2 http://www.worldscinet.com/ijfcs/13/1302/S0129054102001102.html db/journals/ijfcs/ijfcs13.html#AichholzerAH02