"Arithmetica" by Diophantus. English translation is contained in T. L. Heath, Diophantus of Alexandria. A Study in the History of Greek Algebra. For other translations see e.g. [http://web.math.pmf.unizg.hr/~duje/refclas.html][1] [1]: http://web.math.pmf.unizg.hr/~duje/refclas.html