Herstein 1975, §2, pp. 26 Hall 1967, §1.1, pp. 1: "The idea of a group is one which pervades the whole of mathematics both pure and applied."
هيرستاين 1975, قسم 2، ص 26 هول 1967, قسم 1.1، ص 1: "The idea of a group is one which pervades the whole of mathematics both pure and applied."