... IntroductionThe notion of variational bicomplexes was introduced in studying the problem of characterizing the kernel and image of Euler-Lagrange mapping in the calcu-lus of variations. This problem ... 1979.5. D. Krupka, Variational Sequences on Finite Order Jet Spaces, World Scientific,Singapore, (1990) 236–254.6. F. Takens, A global version of the inverse problem of the calculus of variations,J. ... I. M. Anderson, Aspect of the inverse problem to the calculus of variation, Arch.Math. 24 (1988) 181–202.2. I.M. Anderson and T. Duchamp, On the existence of global variational principles,Amer....