Jets with Two Fluids II: Two Free Boundaries Hans AltLuis CaffarelliAvner Friedman Indiana University Mathematics Journal 1984 text pdf 10.1512/iumj.1984.33.33021 10.1512/iumj.1984.33.33021 en Indiana Univ. Math. J. 33 (1984) 367 - 391 state-of-the-art mathematics http://iumj.org/access/