I.L.H. (24 December 2011). "El ferrocarril que perdió el Norte" [The railway that lost its bearing]. Diario de Burgos (in Spanish). Retrieved 27 February 2012.
Olaizola Elordi, Juanjo (5 February 2012). "Trabajo forzado y ferrocarril" [Forced labor and railway] (PDF). El Diario Montañes (in Spanish). Archived from the original(PDF) on 15 June 2012. Retrieved 27 February 2012.
Santos y Ganges, Luis. "Ferrocarril y Territorio: El caso de la sección 7º del Santander-Mediterráneo" [Rail and Territory: The case of section 7 of the Santander-Mediterranean] (PDF). Instituto Universitario de Urbanística de la Universidad de Valladolid (in Spanish). Fundación de Ferrocarriles Españoles. Archived from the original(PDF) on 15 June 2012. Retrieved 27 February 2012.
Cobo, Teresa (9 January 2012). "Travesía bajo tierra por La Engaña" [Underground crossing of the Engaña]. El Diario Montañes (in Spanish). Archived from the original on 16 January 2012. Retrieved 27 February 2012.
Cobo, Teresa (5 February 2012). "El túnel fue la víctima oficial número 17" [The tunnel was the official victim number 17]. El Diario Montañes (in Spanish). Archived from the original on 16 February 2012. Retrieved 27 February 2012.
Cobo, Teresa (25 September 2011). "El agujero negro entre Cantabria y Burgos" [The black hole between Cantabria and Burgos]. El Diario Montañes (in Spanish). Retrieved 27 February 2012.
Cobo, Teresa (13 November 2011). "Unidos por el túnel medio siglo después" [Linked by the tunnel half a century later]. El Diario Montañes (in Spanish). Retrieved 27 February 2012.
"El ferrocarril Santander-Mediterráneo" [The Santander-Mediterranean railway]. Fundación Cultural Eusebio Gómez García y Justina Berdía López (in Spanish). Retrieved 27 February 2012.
issuu.com
"Línea ferroviaria Santander al Mediterráneo" [Railway line Santander to Mediterranean]. ADBAYSE (Advanced Business Actions & Services) (in Spanish). issuu.com. Retrieved 27 February 2012.
Cobo, Teresa (9 January 2012). "Travesía bajo tierra por La Engaña" [Underground crossing of the Engaña]. El Diario Montañes (in Spanish). Archived from the original on 16 January 2012. Retrieved 27 February 2012.
Olaizola Elordi, Juanjo (5 February 2012). "Trabajo forzado y ferrocarril" [Forced labor and railway] (PDF). El Diario Montañes (in Spanish). Archived from the original(PDF) on 15 June 2012. Retrieved 27 February 2012.
Cobo, Teresa (5 February 2012). "El túnel fue la víctima oficial número 17" [The tunnel was the official victim number 17]. El Diario Montañes (in Spanish). Archived from the original on 16 February 2012. Retrieved 27 February 2012.
Santos y Ganges, Luis. "Ferrocarril y Territorio: El caso de la sección 7º del Santander-Mediterráneo" [Rail and Territory: The case of section 7 of the Santander-Mediterranean] (PDF). Instituto Universitario de Urbanística de la Universidad de Valladolid (in Spanish). Fundación de Ferrocarriles Españoles. Archived from the original(PDF) on 15 June 2012. Retrieved 27 February 2012.
