Fanjul, J. 1973. “Methods for the Determination of Silicilic Acid With Anhydrous Acetic Acid, Calcium and Magnesium Oxide With Complexon III in Hydraulic Cements”. Materiales De Construcción 23 (149):85-90. https://doi.org/10.3989/mc.1973.v23.i149.1402.