1. On the energy and length of a knot, Special Session on Physical Knot Theory;Buck,1996
2. Riemannian Geometry;do Carmo,1992
3. Geometria Riemanniana;do Carmo,1979
4. Geometria Riemanniana;do Carmo,1988
5. Y. Diao, K. Ernst and E.J.J. Van Rensburg, Energies of knots, Preprint (3/95); Knot energies by ropes, Preprint (4/96).