Serrano Martínez, E., Giráldez García, F., Lavín González, P., Bernués Jal, A., Bernués Jal, A., & Ruiz Mantecón, A. (2004). The identification of homogeneous groups of cattle farms in the mountains of León, Spain. Spanish Journal of Agricultural Research, 2(4), 512-523. https://doi.org/10.5424/sjar/2004024-107