http://www.sidalc.net/es/inicio

Alianza de Servicios de Información or Alliance of Information Services (SIDALC) facilitates access to information produced in the Americas.  This information is housed and organized in agricultural institutions, their libraries and other centers of related information. It makes available over 3.1 million resources, including books, magazines, thesis and reports, as well as over 240,000 complete text documents.  This service is free and bilingual – Spanish / English.