  A joint source-channel coding (JSCC) scheme based on hybrid digital/analog
coding is proposed for the transmission of correlated sources over
discrete-memoryless two-way channels (DM-TWCs). The scheme utilizes the
correlation between the sources in generating channel inputs, thus enabling the
users to coordinate their transmission to combat channel noise. The hybrid
scheme also subsumes prior coding methods such as rate-one separate
source-channel coding and uncoded schemes for two-way lossy transmission, as
well as the correlation-preserving coding scheme for (almost) lossless
transmission. Moreover, we derive a distortion outer bound for the
source-channel system using a genie-aided argument. A complete JSSC theorem for
a class of correlated sources and DM-TWCs whose capacity region cannot be
enlarged via interactive adaptive coding is also established. Examples that
illustrate the theorem are given.
