Scirus

http://www.scirus.com/srsapp/

Specialized search engines to find academic information.

Scinet

http://www.scinet.cc/

Specialized search engines to find Science, Technologic and Medical resources.

TechXtra

http://www.techxtra.ac.uk/index.html

Specialized search engines to find a wide range of quality articles, books, web locations, news, technical repports and Ph tesis related Engieneering, Math and Computer science areas..

GlobalSpec : the Engineering Search Engine

http://www.globalspec.com/

Specialized search engines to find engieneerig information. .

Google Académico

http://scholar.google.es/

Allows search specialized  information about academic and research areas.

CiteSeer.IST : Scientific Literature Digital Library

http://citeseer.ist.psu.edu/

Specialized search engines to find a wide range of quality articles, books, web locations, news, technical repports and Ph tesis related Engieneering, Math and Computer science areas..

EPrints Complutense

http://www.ucm.es/eprints/

Publications Electronic Server from Universidad Complutense de Madrid (UCM).

DSpace

http://dspace.mit.edu/

Digital file in order to extend all the intelectual production from MIT (Massachussets Institute of Technology): artícles, repprots, comunications, programs,  etc.

arXiv

http://es.arxiv.org/

E-print server for Phisics, Maths, Computer and Biology areas.

RECERCAT : Container of Catalonia Research

http://www.recercat.net/index.jsp

Free acccess container for digital documentation . It include scientific production from Catalonia Universities and Research centers, also preprints, congress comunications, research results, etc.

eprintweb.org

http://eprintweb.org/S/main

Search server for e-prints created for arXiv.org information.

Signal Processing Information Base (SPIB)

http://spib.rice.edu/

Proyect financed by Signal Processing Society and National Science Foundation. We can find lastest information about Signals Processing.

GrayLIT Network

http://www.osti.gov/graylit/

Acces to more than 100.000 technical repports.

NTRS: NASA Technical Reports Server

http://ntrs.nasa.gov/

Specialized search engines to find Science, Technologic and Medical resources.

AENOR

http://www.nssn.org/

National Resource for Global Standards, it has a catalog with more than 250.000 references  from 600 centers

Global Engineering Documents

http://global.ihs.com/

 A Part of Handling Services, IHS, and one of the most world important normative distributors from : ANSI, API, ASME, ASQ, ASTM, BSI, CSA, IEEE, ISO, SAE...

ISO International Organization for Standardization

http://www.iso.org/iso/en/ISOOnline

Web of International Organization for Standardization,