WITNESS

Risālah ilá al-ustādh al-fāḍil Abī Muḥammad ʿAbd Allāh al-Ḥāsib fī al-dalālah ʿalá ṭarīqay al-ustādh Abī Sahl al-Kūhī al-muhandis wa-al-sheikh Abī Ḥāmid al-Ṣaghānī wa-ṭarīqihi allatī salakahā fī ʿamal al-musabbaʿ al-mutasāwī al-aḍlāʿ fī al-dāʾirah_Oxford_