Fiey, Jean Maurice, Mossoul chrétienne: Essais sur l’histoire, archéologie et l’état actuel des monumenys chrétiens de la ville de Mossoul, Beyrouth 1959, 164 pp;
There are many articles and dissertation theses in Turkish. You can search and read in Turkish. The journals and books in Turkiye have also a few articles in Arabic about Medieval Mousul and its architecture. For example: