J.-J. Nájera-Sánchez, E.-M. Mora-Valentín, M. Ortiz-de-Urbina-Criado, and P. Moura-Díez, “Mapping the conceptual structure of environmental management: a co-word analysis”, BTP, vol. 20, pp. 69–80, Feb. 2019, doi: 10.3846/btp.2019.07.