  Antiproton annihilations on nuclei provide a very interesting way to study
the behaviour of strange particles in the nuclear medium. In low energy $\bar
p$ annihilations, the hyperons are produced mostly by strangeness exchange
mechanisms. Thus, hyperon production in $\bar p A$ interactions is very
sensitive to the properties of the antikaon-nucleon interaction in nuclear
medium. Within the Giessen Boltzmann-Uehling-Uhlenbeck transport model (GiBUU),
we analyse the experimental data on $\Lambda$ and $K^0_S$ production in $\bar p
A$ collisions at $p_{\rm lab}=0.2-4$ GeV/c. A satisfactory overall agreement is
reached, except for the $K^0_S$ production in $\bar p+^{20}$Ne collisions at
$p_{\rm lab}=608$ MeV/c, where we obtain substantially larger $K^0_S$
production rate. We also study the $\Xi$ hyperon production, important in view
of the forthcoming experiments at FAIR and J-PARC.
