* "The Ribats in Morocco and their influence in the spread of knowledge and tasawwuf" from: "al-Imra'a al-Maghribiyya wa't-Tasawwuf" (The Moroccan Woman and Tasawwuf in the Eleventh Century) by Mustafa 'Abdu's-Salam al-Mahmah)* Ribat of Soussa, Muslim invention of rib vaulting?
* «The Ribats in Morocco and their influence in the spread of knowledge and tasawwuf» from: "al-Imra’a al-Maghribiyya wa’t-Tasawwuf" (The Moroccan Woman and Tasawwuf in the Eleventh Century) by Mustafa 'Abdu’s-Salam al-Mahmah)* Ribat of Soussa, Muslim invention of rib vaulting?