Victor J. Katz, STAGES IN THE HISTORY OF ALGEBRA WITH IMPLICATIONSFOR TEACHING (PDF), in VICTOR J.KATZ, University of the District of Columbia Washington DC, USA, p. 190. URL consultato il 7 ottobre 2017 (archiviato dall'url originale il 27 marzo 2019). Ospitato su University of the District of Columbia Washington DC, USA.
«The first true algebra text which is still extant is the work on al-jabr and al-muqabala by Mohammad ibn Musa al-Khwarizmi, written in Baghdad around 825.»