@article{10_4153_CMB_1988_026_6,
     author = {Jimenez, J. Alfredo},
     title = {The {Focal} {Locus} of a {Riemannian} {4-Symmetric} {Space}},
     journal = {Canadian mathematical bulletin},
     pages = {175--181},
     year = {1988},
     volume = {31},
     number = {2},
     doi = {10.4153/CMB-1988-026-6},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-1988-026-6/}
}