P. Harjulehto y P. Hästö, «A capacity approach to the Poincaré inequality and Sobolev imbeddings in variable exponent Sobolev spaces»., Rev. mat. complut., vol. 17, n.º 1, pp. 129–146, jun. 2004, doi: https://doi.org/10.5209/rev_REMA.2004.v17.n1.16790