"Los primeros años de foot-ball en Bilbao" [The first years of football in Bilbao]. memoriasclubdeportivodebilbao.blogspot.com (in Spanish). 8 September 2016. Archived from the original on 31 March 2022. Retrieved 20 July 2022.
"Los primeros años de foot-ball en Bilbao" [The first years of football in Bilbao]. memoriasclubdeportivodebilbao.blogspot.com (in Spanish). 8 September 2016. Archived from the original on 31 March 2022. Retrieved 20 July 2022.