Selge, Florian, Heinrich Hagel, Günter Gunkel, and Reiner Doluschitz. “ANNUAL RAINFALL VARIABILITY AND ECONOMICAL DEPENDENCY OF SMALLHOLDER AGRICULTURE IN THE SEMI-ARID NORTHEASTERN REGION OF BRAZIL”. Revista Brasileira de Ciências Ambientais, no. 36 (June 30, 2015): 155–167. Accessed February 3, 2025. https://www.rbciamb.com.br/Publicacoes_RBCIAMB/article/view/197.