  Reliable transmission of arbitrarily correlated sources over multiple-access
relay channels (MARCs) and multiple-access broadcast relay channels (MABRCs) is
considered. In MARCs, only the destination is interested in a reconstruction of
the sources, while in MABRCs, both the relay and the destination want to
reconstruct the sources. We allow an arbitrary correlation among the sources at
the transmitters, and let both the relay and the destination have side
information that are correlated with the sources.
  Two joint source-channel coding schemes are presented and the corresponding
sets of sufficient conditions for reliable communication are derived. The
proposed schemes use a combination of the correlation preserving mapping (CPM)
technique with Slepian-Wolf (SW) source coding: the first scheme uses CPM for
encoding information to the relay and SW source coding for encoding information
to the destination; while the second scheme uses SW source coding for encoding
information to the relay and CPM for encoding information to the destination.
