STUDIES ON THE LEGEND OF THE HOLY GRAIL: WITH SPECIAL REFERENCE TO THE HYPOTHESIS OF ITS CELTIC ORIGIN ALFRED NUTT 1888
SERPENTS OF FIRE: NAZI FLYING SAUCERS, THE HOLY GRAIL, AND THE HITLER/HOLLOW EARTH CONNECTION FLORIA BENTON 1983
THE OCCULT AND THE THIRD REICH: THE MYSTICAL ORIGINS OF NAZISM AND THE SEARCH FOR THE HOLY GRAIL JEAN–MICHEL ANGEBERT 1974
THE HIDDEN CHURCH OF THE HOLY GRAAL: ITS LEGENDS AND SYMBOLISM CONSIDERED IN THEIR AFFINITY WITH CERTAIN MYSTERIES OF INITIATION AND OTHER TRACES OF A SECRET TRADITION IN CHRISTIAN TIMES ARTHUR EDWARD WAITE 1909
THE HOLY GRAAL AND OTHER FRAGMENTS; BEING THE UNCOMPLETED PARTS OF THE ARTHURIAN DRAMAS RICHARD HOVEY 1907
MYSTIC GLEAMS FROM THE HOLY GRAIL: THE LEGEND OF SPIRITUAL CHIVALRY, THE MYSTERY OF ITS DIVINE ORIGIN, ITS SECRET IN THE WORLD OF FAERIE AND ITS HIGH INITIATION FRANCIS ROLT-WHEELER 1948