JONDRUP, S. Rings in Which Pure Ideals are Generated by Idempotents. Mathematica Scandinavica, Berkeley, CA, United States, v. 30, p. 177–185, 1972. DOI: 10.7146/math.scand.a-11073. Disponível em: https://journals.msp.org/mscand/article/view/2256. Acesso em: 25 jul. 2026.