Kessler, K. Mani (Berlin, 1889 and 1903); article "Mani und die Manichäer" (in Herzog-Hauck's Real-Encyklopädie) (Leipzig, 1903).
Kugener and Cumont. Recherches sur le manichéisme (Brussels, 1908 ff.)
Druses
Sacy, Silvestre de. Exposé de la religion des Druses (Paris, 1838).
Churchill, C. H. Ten Years' Residence in Mount Lebanon (London, 1853).
Wortabet, J. Researches into the Religions of Syria (London, 1860).
Guys, H. La théogonie des Druses (Paris, 1863).
Herzog-Hauck. Real-Encyklopädie, Index, s.v. Drusen.
Hogarth, D. G., and Bell, Gertrude L. Article "Druses" (in Encyclopædia Britannica, 11th ed.).
Babism and Bahaism