See this legally free ebook:

  • A Handbook of Church Music: a practical guide for all those having the charge of schools and choirs, and others who desire to restore plainsong to its proper place in the services of the Church, by F. Clement C. Egerton, with a preface by H.G. Worth (London: R. & T. Washbourne, c1909). With Imprimatur. Available on Internet Archive (Digitizing sponsor: MSN; Book contributor: Faculty of Music Library, University of Toronto).

In belated observance of the Feast of St. Romanos the Melodist in the Eastern Catholic churches.