@Misc{ CatBel20, author = { Belgiorno, Francesco and Catino, Giovanni }, title = { A Weyl Entropy of Pure Spacetime Regions }, journal = { Class. Quantum Grav. }, year = { 2020 }, doi = { https://doi.org/10.1088/1361-6382/abb958 }, pages = { }, URL = { http://cvgmt.sns.it/paper/4668/ }, note = { cvgmt preprint} }