Thermolysis of C[sub 60] thin films yields Ni-filled tapered nanotubes. - Grobert, N.; Terrones, M.; Osborne, A.J.; Terrones, H.; Hsu, W.K.; Trasobares, S.; Zhu, Y.Q.; Hare, J.P.; Kroto, H.W.; Walton, D.R.M. (Applied Physics A: Materials Science & Processing, 1998)