Bernal, J. L., del Nozal, J., Deban, L., Tascón, M. L. and Sánchez Cerrato, Ángel (1988) “Determination of sulphides in cements by using potentiometry with a selective electrode of sulphides”, Materiales de Construcción, 38(209), pp. 5–12. doi: 10.3989/mc.1988.v38.i209.844.