@article{10_1017_S001708950003055X,
     author = {Defever, Filip and Deszcz, Ryszard and Verstraelen, Leopold},
     title = {The {Chen-type} of the noncompact cyclides of {Dupin}},
     journal = {Glasgow mathematical journal},
     pages = {71--75},
     year = {1994},
     volume = {36},
     number = {1},
     doi = {10.1017/S001708950003055X},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S001708950003055X/}
}