Thomas Carlson (eds.), "al-Thaghr" in The Beth Qaṭraye Gazetteer last modified January 10, 2020, https://bqgazetteer.bethmardutho.org/place/567
    
        
            
                
                    al-Thaghr
                    الثغر
                    الثَغْر
                    الثغز
                    الثغوز
                    The border area of northern Syria
                        and Mesopotamia between the Byzantine Empire and the caliphate.
                    
                        Attestation of name الثَغْر in the Muʿjam
                                al-buldān of Yāqūt al-Ḥamawī.
                        
                    
                    
                        Attestation of name الثغوز
                            in the Kitāb al-buldān of
                                Aḥmad ibn Abī Yaʿqūb al-Yaʿqūbī.
                        
                    
                    
                        
                        
                    
                    https://bqgazetteer.bethmardutho.org/place/567
                    http://syriaca.org/place/567
                    
                        كتاب اللؤلؤ المنثور في تاريخ العلوم والأداب
                            السريانية
                        
                        511
                    
                    
                        The Scattered Pearls: A History of Syriac
                            Literature and Sciences
                        
                        569
                    
                    
                        Muʿjam al-buldān
                        Yāqūt al-Ḥamawī
                        
                        II93
                    
                    
                        Kitāb al-buldān
                        Aḥmad ibn Abī Yaʿqūb al-Yaʿqūbī
                        
                        237