González-Perea, L., J. Hernández-Galán, and N. González Villariny. “The Presence of Universal Accessibility in Doctoral Dissertations Deposited in Spain Between 1998-1999 and 2017-2018 Academic Years”. Journal of Accessibility and Design for All, Vol. 9, no. 2, Nov. 2019, pp. 118 -40, doi:10.17411/jacces.v9i2.213.