@article{MAN_1985__273_164044,
     author = {Wilhelm Jr. Klingenberg},
     title = {Asymptotic {Curves} on {Real} {Analytic} {Surfaces} in {C2.}},
     journal = {Mathematische Annalen},
     pages = {149--162},
     publisher = {mathdoc},
     volume = {273},
     year = {1985},
     zbl = {0607.32006},
     url = {http://geodesic.mathdoc.fr/item/MAN_1985__273_164044/}
}