See this legally free ebook:
- The Greek Fathers, by Adrian Fortescue (London, Catholic Truth Society; St. Louis, MO: B. Herder, 1908). With Imprimatur. Available in various formats (epub, pdf, kindle/mobi, etc.) at Internet Archive, with a 2nd copy at Internet Archive, and a 3rd copy at Internet Archive; and also available at HathiTrust Digital Library.
On the Memorial of Saint Basil the Great and Saint Gregory Nazianzen in the Ordinary Form of the Roman Rite. For other legally free ebooks, you may access the List of Free eBooks (Arranged by Title) and the List of Free eBooks (Grouped by Subject).