Taylor Expansion of Bessel Potentials Norman Meyers Indiana University Mathematics Journal 1974 text pdf 10.1512/iumj.1974.23.23085 10.1512/iumj.1974.23.23085 en Indiana Univ. Math. J. 23 (1974) 1043 - 1049 state-of-the-art mathematics http://iumj.org/access/