Citation: Vl. Erhart, THE CHURCH OF THE EAST DURING THE PERIOD OF THE 4 RIGHTLY-GUIDED CALIPHS -CENTURY( INTERNAL QUARRELS OF THE SYRIAC CHRISTIAN COMMUNITY IN THE SASANIAN EMPIRE DURING THE EARLY 7TH), Bulletin of the John Rylands University Library of Manchester, 78(3), 1996, pp. 55-71