storia medievale TecaLibri John L. Sorenson: opere 1996 Pre-Columbian Contact with the Americas across the Oceans: An Annotated Bibliography, Research Press, Provo, 2 voll., [rif.] con: Martin H. Raish 2009 World Trade and Biological Exchanges Before 1492, iUniverse, Bloomington, [rif.] con: Carl L. Johannessen