A Comparison of the Scientific Performance of the U.S. and the European Union at the Turn of the XXI Century Albarran, P., J. Crespo, I. Ortuño and J. Ruiz-CastilloScientometrics – 2010 24 de octubre de 2015Pub, PubFac, PubFacAlbarranP, Pubfield, PubfieldEconometrics, Pubyear2010Por coralio