"Review"(PDF). Coptic Church Review. Vol. 22, no. 1. Primavera. 2001. p. 19. ISSN0273-3269. Archived from the original(PDF) on 8 July 2011. Retrieved 17 April 2012.[dead link]
Wolfgang Kosack, Die „Bibliothek Goussen". Eine orientalische Spezialbibliothek in der Universitätsbibliothek Bonn. Kolonia, Bibliothekar-Lehrinstitut des Landes Nordrhein-Westfalen, tesi per l'esame di operatore civile di alto livello, 1973 (Digitalizzato)
"Review"(PDF). Coptic Church Review. Vol. 22, no. 1. Primavera. 2001. p. 19. ISSN0273-3269. Archived from the original(PDF) on 8 July 2011. Retrieved 17 April 2012.[dead link]
worldcat.org
"Review"(PDF). Coptic Church Review. Vol. 22, no. 1. Primavera. 2001. p. 19. ISSN0273-3269. Archived from the original(PDF) on 8 July 2011. Retrieved 17 April 2012.[dead link]