Chinchilla Picado, M., Barrientos, Z. and Calderón, K. 2016. The environmental education workshop as a teaching strategy for sustainability of natural resources in rural Costa Rican elementary schools. UNED Research Journal. 8, 2 (Oct. 2016), 157–161. DOI:https://doi.org/10.22458/urj.v8i2.1555.