Check out:

  • The Three Ages of the Interior Life, by Reginald Garrigou-Lagrange, O.P. On Prayer and Spirituality. May be read online on Christian Perfection, accessed through Catholic Treasury. [According to the website, The summary of a course in ascetical and mystical theology given for over 20 years at the Angelicum in Rome]

For more legally free ebooks, visit the Catholic eBooks Project.