@article{10_5427_jsing_2015_12c,
     author = {Goo Ishikawa and Yoshinori Machida, and Masatomo Takahashi},
     title = {Geometry of {D_4} conformal triality and singularities of tangent surfaces},
     journal = {Journal of Singularities},
     pages = {27--52},
     publisher = {mathdoc},
     volume = {12},
     year = {2015},
     doi = {10.5427/jsing.2015.12c},
     url = {http://geodesic.mathdoc.fr/articles/10.5427/jsing.2015.12c/}
}