The congruence of tangents to a system of curves on a surface
Compositio Mathematica, Tome 13 (1956-1958), pp. 247-256 
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     author = {Kamalamma, K. N.},
     title = {The congruence of tangents to a system of curves on a surface},
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     pages = {247--256},
     year = {1956-1958},
     publisher = {Kraus Reprint},
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     mrnumber = {104237},
     zbl = {0099.37103},
     language = {en},
     url = {https://www.numdam.org/item/CM_1956-1958__13__247_0/}
}
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Kamalamma, K. N. The congruence of tangents to a system of curves on a surface. Compositio Mathematica, Tome 13 (1956-1958), pp. 247-256. https://www.numdam.org/item/CM_1956-1958__13__247_0/

C.E. Weatherburn, [1] Differential geometry Vol. 1, page 185.

C.E. Weatherburn, [2] Differential geometry, Vol. 1, page 185.

C.E. Weatherburn, [3] Differential geometry, Vol. 1, page 192.

C.F. Weatherburn, [4] Differential geometry, Vol. 1, page 91.

C.N. Srinivasiengar, [5] Proc. Indian Acad. Sc. Vol. XII. 1940, page 352.

C.E. Weatherburn, [6] loc. cit. page 91.

C.E. Weatherburn, [7] loc. cit. page 205.

Behari Ram, [8] Lectures on Differential geometry of Ruled Surfaces. Page 59.

Behari Ram, [9] Lectures on Differential geometry of Ruled Surfaces. Page 61.

K.N. Kamalamma, Journal of the Mysore University. Vol. XV - page 51.

L.P. Eisenhart, [10] Differential Geometry 1909. Page 403.

C.E. Weatherburn, [11] loc. cit. Page 205.

C.E. Weatherburn, [12] loc. cit. Page 205.

Bianchi, [13] Geometria, differenziale. Vol. I, page 472.