@book {Artes07book, title = {Comunicaciones Digitales}, year = {2007}, month = {May}, publisher = {Pearson - Prentice Hall}, organization = {Pearson - Prentice Hall}, author = {Antonio Art{\'e}s-Rodr{\'\i}guez and Fernando P{\'e}rez-Gonz{\'a}lez and Jes{\'u}s Cid-Sueiro and R. L{\'o}pez-Valcarce and C. Mosquera and Fernando P{\'e}rez-Cruz} }