@article{MAN_1983__263_163729,
     author = {L. Vanhecke and T.J. Willmore},
     title = {Interaction of {Tubes} and {Spheres.}},
     journal = {Mathematische Annalen},
     pages = {31--42},
     publisher = {mathdoc},
     volume = {263},
     year = {1983},
     zbl = {0491.53034},
     url = {http://geodesic.mathdoc.fr/item/MAN_1983__263_163729/}
}