Ramirez Lopez, L., Behrens, T., Schmidt, K., Stevens, A., Demattê, J. A., & Scholten, T. (2013). The spectrum-based learner: a new local approach for modeling soil vis-NIR spectra of complex datasets. Geoderma, 195-196, 268-279. https://doi.org/10.1016/j.geoderma.2012.12.014 (Original work published 2013)