Ellsberg's rhymes with:
belzbergs', belzbergs', belzbergs', gettysburg's, ginsburg's, kongsberg's, ransburg's, belzbergs, belzbergs', bloomberg's, fogelberg's, forsburg's, freeberg's, freedenberg's, gettysburg's, ginsburg's, goldberg's, greenberg's, harrisburg's, harrisburgh's, heidelberg's, hoffenberg's, hopburg's, icebergs, johannesburg's, katzenberg's, kelberg's, kohlberg's, kongsberg's, nashburg's, pittsburgh's, ransburg's, rittenberg's, rosenberg's, rosenbergs, schwartzberg's, spielberg's, steinberg's, thornburg's, thornburgh's, thornburghs, thornburgs, wallenberg's, warburg's
Ellsberg's sounds like:
ellsberg, ellsburg, elsevier's