Martin-Loeches, Miguel, et al. “Hydrogeological Survey Methodology and Set Wells Drilled With a Hand Pump. Application in the Region Crystal Caimbambo (Benguela, Angola)”. M+A. Revista Electrónica de Medioambiente, vol. 16, no. 1, July 2015, pp. 13-33, https://doi.org/10.5209/rev_MARE.2015.v16.n1.49592.