Berry phase and de Haas - van Alphen effect in LaRhIn₅

We explain the experimental data on the magnetization of $LaRhIn_5$ recently published by R. G. Goodrich et al. in Phys. Rev.Lett. {\bf 89}, 026401 (2002). We show that the magnetization of a small electron group associated with a band-contact line was detected in that paper. These data provide the first observation of the Berry phase of electrons in metals via the de Haas - van Alphen effect.