Thomas A. Carlson (ed.), "Gissā" in last modified January 14, 2014, http://syriaca.org/place/1229
    
        
            
                
                    Gissā
                    
                    
                        Tḥūmā district
                        Hakkārī region
                    
          
                    http://syriaca.org/place/1229
                    
                        David Wilmshurst
                        The Ecclesiastical Organisation of the Church of the East, 1318-1913
                        105, 139, 140, 151, 297, 298