Uniqueness and Nonuniqueness of the Plateau Problem Fang-Hua Lin Indiana University Mathematics Journal 1987 text pdf 10.1512/iumj.1987.36.36045 10.1512/iumj.1987.36.36045 en Indiana Univ. Math. J. 36 (1987) 843 - 848 state-of-the-art mathematics http://iumj.org/access/