  Shubnikov-de Haas (SdH) oscillations and upper critical magnetic field
($H\_{c2}$) of the iron-based superconductor FeSe ($T\_c$ = 8.6 K) have been
studied by tunnel diode oscillator-based measurements in magnetic fields of up
to 55 T and temperatures down to 1.6 K. Several Fourier components enter the
SdH oscillations spectrum with frequencies definitely smaller than predicted by
band structure calculations indicating band renormalization and reconstruction
of the Fermi surface at low temperature, in line with previous ARPES data. The
Werthamer-Helfand-Hohenberg model accounts for the temperature dependence of
$H\_{c2}$ for magnetic field applied both parallel (\textbf{H} $\|$ $ab$) and
perpendicular (\textbf{H} $\|$ $c$) to the iron conducting plane, suggesting
that one band mainly controls the superconducting properties in magnetic fields
despite the multiband nature of the Fermi surface. Whereas Pauli pair breaking
is negligible for \textbf{H} $\|$ $c$, a Pauli paramagnetic contribution is
evidenced for \textbf{H} $\|$ $ab$ with Maki parameter $\alpha$ = 2.1,
corresponding to Pauli field $H\_{P}$ = 36.5 T
