Miguel de Unamuno: Spanish Educator, Philosophy, and Author
https://www.britannica.com/biography/Miguel-de-Unamuno
This website is a full, in-depth biography of Miguel de Unamuno, the author of San Manuel Bueno, Martyr.
Unamuno was a man 'burdened with wisdom rather than with knowledge'
https://www.ncronline.org/blogs/ncr-today/unamuno-was-man-burdened-wisdom-rather-knowledge
This article details the spiritual and religious struggle that Miguel de Unamuno personally experienced in his real life.