For a proposal from 2003 by the then Governor Bernanke, see Ben S. Bernanke (2003), “Panel Discussion,” speech delivered at the 28th Annual Policy Conference: Inflation Targeting Prospects and Problems, Federal Reserve Bank of St. Louis, St. Louis, Missouri, October 17.
My own thinking on the issue has evolved over the years; for a snapshot of its state in early 2006, see Janet L. Yellen (2006), “Enhancing Fed Credibility,” speech delivered at the Annual Washington Policy Conference Sponsored by the National Association for Business Economics, Washington, March 13.