Fanjul, J. “Methods for the Determination of Silicilic Acid With Anhydrous Acetic Acid, Calcium and Magnesium Oxide With Complexon III in Hydraulic Cements”. Materiales De Construcción, vol. 23, no. 149, Mar. 1973, pp. 85-90, doi:10.3989/mc.1973.v23.i149.1402.