@article{MAN_1985__271_163985,
     author = {R. Ganong and P. Russell},
     title = {The {Tangent} {Bundle} of a {Ruled} {Surface.}},
     journal = {Mathematische Annalen},
     pages = {527--548},
     publisher = {mathdoc},
     volume = {271},
     year = {1985},
     zbl = {0541.14035},
     url = {http://geodesic.mathdoc.fr/item/MAN_1985__271_163985/}
}