Miranda, M. J. de, C. Costa, P. Santana, and L. V. Barrozo. “Spatial Association Between Socioeconomic Variables and Risk Related to Pre-Term Births in Metropolitan Region of Sao Paulo (MRSP) and Lisbon Metropolitan Area (AML)”. Saúde E Sociedade, vol. 23, no. 4, Dec. 2014, pp. 1142-53, doi:10.1590/S0104-12902014000400002.