Triebel-Lizorkin spaces on metric spaces via hyperbolic fillings Mario BonkEero SaksmanTomás Soto Indiana University Mathematics Journal 2018 text pdf 10.1512/iumj.2018.67.7282 10.1512/iumj.2018.67.7282 en Indiana Univ. Math. J. 67 (2018) 1625 - 1663 state-of-the-art mathematics http://iumj.org/access/