Cardinality of Generating Sets for Ideals of a Commutative Ring Robert GilmerWilliam Heinzer Indiana University Mathematics Journal 1977 text pdf 10.1512/iumj.1977.26.26062 10.1512/iumj.1977.26.26062 en Indiana Univ. Math. J. 26 (1977) 791 - 798 state-of-the-art mathematics http://iumj.org/access/