respect to the plane (it is a quadrupole). This is in the agreement with the galactic dynamo model, which is briefly discussed in the next paragraph.]{}

Other facts used in modelling of GMF have indirect character — they are usually derived from the observations of the other spiral galaxies and of the structure of their magnetic fields or from existing hypothesis of the mechanisms of magnetic field generation. In general, it is expected, that the Galactic magnetic field encompasses the entire Galactic disk and shows some spiral structure. Further research and measurements in this field have vital importance not only for the observations of UHECRs, but also for the whole cosmic-ray physics and for other astronomical applications, e.g. for Galactic dynamics.

Theoretical global models of GMF {#gmf}
--------------------------------

The global models omit the presence of turbulent fields and they are trying to model just the regular component. The basic conservative model of global Galactic plane was established by [@hanold], based on the Faraday-rotation measurements of 134 pulsars. The model assumes a two-arm logarithmic spiral with the constant pitch angle[^3] $p$ and it shows $\pi$-symmetry, so that it is bisymmetric (BSS) magnetic field model. More exactly, it has also a dipole 