Albeverio, Sergio A., Shavkat A. Ayupov, y Bakhrom A. Omirov. 2006. «Root Arrangements of Hyperbolic Criterion of Solvability of Finite Dimensional Leibniz Algebras». Revista Matemática Complutense 19, nº 1: 197-225. https://doi.org/10.5209/rev_REMA.2006.v19.n1.16654