Τρισάγιον – in the Byzantineand Old Bulgarian Liturgical Practice. Characteristics, Features and Use in the Liturgical Tradition of the Church. FThS [интернет]. 22 Май 2025 [цитиран 15 Октомври 2025];(1):7-60. достъпен на: https://periodicals.uni-sofia.bg/index.php/forum-theologicum-sardicense/article/view/408