         <a href="#references">9. References</a>
        </li>
      </ul>
    </div>
    <h2>
      <a name="intro">1. Introduction</a>
    </h2>
    <p>
    X-splines (<a href="#blanc+schlick">Blanc and Schlick, 1995</a>)
    are a family of curves defined by control points (like a Bezier curve),
    with a shape parameter at each control point that allows the curve
    to vary between interpolation and approximation at each control point.
    In the diagram below, there are three X-splines, each drawn re