[635] Giorn. di Matem. 17; Lincei Rend. 1879.

[636] Torino Atti, 1881.

[637] Journ. für Math. 91, 92, 93, 94, 95, 97.

[638] The Messenger of Mathematics II, 13.

[639] Liouvilles Journ. II, 17.

[640] S. Note [629].

[641] Math. Ann. 5.

[642] Ann. Éc. norm. II, 6; Grunerts Arch. 40.

[643] Ann. Éc. norm. III, 1.

[644] S. Note [628].