[1] E. Cartan: Lecons sur les invariants intégraux. Hermann, Paris, 1922. MR 0355764

[2] H. Goldschmidt S. Sternberg: The Hamilton-Cartan formalism in the calculus of variations. Ann. Inst. Fourier, Grenoble, 23 (1973), 203-267. DOI 10.5802/aif.451 | MR 0341531

[3] R. Hermann: Geometry, Physics and Systems. Dekker, New York, 1973. MR 0494183 | Zbl 0285.58001

[4] I. Kolář: On the hamilton formalism in fibered manifolds. Scripta Fac. Sci. Nat. UJЕР Brunensis, Physica 3-4 (1975), 249-254. MR 0442978

[5] D. Krupka: A geometric theory of ordinary first order variational problems in fibred manifolds. I. Critical sections. J. Math. Anal. Appl. 49 (1975), 180-206. DOI 10.1016/0022-247X(75)90169-9 | MR 0362397

[6] D. Krupka: Some geometric aspects of variational problems in fibred manifolds. Folia Fac. Sci. Nat. Univ. Brunensis, XIV, 10, 1973.

[7] Th. H. J. Lepage: Sur les champs géodésiques du Calcul des Variations. Bull. Acad. Roy. Belg. Cl. Sci. V, 22 (1936), 716-729, 1036-1046. Zbl 0016.26201

[8] J. Śniatycki: On the geometric structure of classical field theory in Lagrangian formulation. Proc. Cambridge Philos. Soc. 68 (1970), 475-484. MR 0261936