Open Textbook Library
https://open.umn.edu/opentextbooks https://biblio.udb.edu.sv/biblioteca/wp-content/uploads/2023/06/OTL.png
Libros electrónicos
Digitalia
https://www.digitaliapublishing.com/ https://biblio.udb.edu.sv/biblioteca/wp-content/uploads/2023/05/digitalia.png
Literatura Religiosa
/biblioteca/index.php/pastoral https://biblio.udb.edu.sv/biblioteca/wp-content/uploads/2022/09/Logos-RE-sitio-web-UDB.png
MIT Press Direct
https://direct.mit.edu/books/search-results?f_ContentType=Book&fl_SiteID=5&access_openaccess=true https://biblio.udb.edu.sv/biblioteca/wp-content/uploads/2022/08/15.png
Taylor & Francis Group
https://www.taylorfrancis.com/search?key=a&openAccess=true https://biblio.udb.edu.sv/biblioteca/wp-content/uploads/2022/05/Captura-de-pantalla-2023-07-14-082140.png
Springer Link
https://link.springer.com/search/page/2?facet-content-type=%22Book%22&from=SL&showAll=false https://biblio.udb.edu.sv/biblioteca/wp-content/uploads/2021/06/12.jpg
Intech Books
https://www.intechopen.com/books https://biblio.udb.edu.sv/biblioteca/wp-content/uploads/2021/06/11.jpg
FreeTechBooks
https://www.freetechbooks.com/ https://biblio.udb.edu.sv/biblioteca/wp-content/uploads/2021/06/10.jpg
Directory of Open Access Books
https://www.doabooks.org/ https://biblio.udb.edu.sv/biblioteca/wp-content/uploads/2021/06/9.jpg
Project MUSE
https://muse.jhu.edu/browse/titles/all?browse_view_type=list&limit_content_type=book /biblioteca/wp-content/uploads/2021/06/8.jpg
Knovel
https://app.knovel.com/kn https://biblio.udb.edu.sv/biblioteca/wp-content/uploads/2022/08/16.png
E-libro
https://elibro.net/es/lc/cbues/inicio https://biblio.udb.edu.sv/biblioteca/wp-content/uploads/2023/01/14.jpeg
