Sertucha, J., R. Suárez, J. Legazpi, and P. Gacetabeitia. “Influence of Moulding Conditions and Mould Characteristics on the Contraction Defects Appearance in Ductile Iron Castings”. Revista De Metalurgia, vol. 43, no. 3, June 2007, pp. 188-95, doi:10.3989/revmetalm.2007.v43.i3.64.