“…In our particular case, the variables Ω 1 , Ω 2 , ω 1 , ω 2 , ω 3 correspond to (more precisely, are dual 1 All Poisson brackets of rank two are described in a recent paper by A. Yu. Konyaev [Konyaev, 2014]. The issue of classification of such brackets was raised in [Bolsinov et al, 2012], where the following question was also formulated: "Are there any Hamiltonian systems with brackets that do not admit globally defined independent n − 1 integrals?".…”