Grigor’yan, A., and I. Verbitsky. “Pointwise Estimates of Solutions to Nonlinear Equations for Nonlocal Operators ”. ANNALI SCUOLA NORMALE SUPERIORE - CLASSE DI SCIENZE, vol. 20, no. 2, May 2020, pp. 721-50, doi:10.2422/2036-2145.201802_011.