  Electron transport through the Corbino disk in graphene is studied in the
presence of uniform magnetic fields. At the Dirac point, we observe conductance
oscillations with the flux piercing the disk area $\Phi_d$, characterized by
the period $\Phi_0=(2h/e)\ln(R_o/R_i)$, where $R_o$ ($R_i$) is the outer
(inner) disk radius. The oscillations magnitude increase with the radii ratio
and exceed 10% of the average conductance for $R_o/R_i\geqslant 5$ in the case
of the normal Corbino setup, or for $R_o/R_i\geqslant 2.2$ in the case of the
Andreev-Corbino setup. At a finite but weak doping, the oscillations still
appear in a limited range of $|\Phi_d|\leqslant\Phi_d^{max}$, away from which
the conductance is strongly suppressed. At large dopings and weak fields we
identify the crossover to a normal ballistic transport regime.
