On the possibility of estimating chemically the pozzolanic activity of a material added to Portland cement : proposal to the Technical Committee ISO/74 /
Goria, C.
Negro, A.
Garston :  Building Research Station, 
1970.
Originally published as Sulla possibilita di verificare chimicamente la reattivita pozzolanica di un materiale aggiunto al Portland, in L'Industria Italiana del Cemento, 1963, 33 (7), 491-8.