The tangency of a C^1 smooth submanifold with respect to a non-involutive C^1 distribution has no superdensity points Silvano Delladio Indiana University Mathematics Journal 2019 text pdf 10.1512/iumj.2019.68.7549 10.1512/iumj.2019.68.7549 en Indiana Univ. Math. J. 68 (2019) 393 - 412 state-of-the-art mathematics http://iumj.org/access/