Approximating Compact Inner Metric Spaces by Surfaces Mark Cassorla Indiana University Mathematics Journal 1992 text pdf 10.1512/iumj.1992.41.41029 10.1512/iumj.1992.41.41029 en Indiana Univ. Math. J. 41 (1992) 505 - 513 state-of-the-art mathematics http://iumj.org/access/