  In this work we study the exact boundary controllability of a generalized
wave equation in a nonsmooth domain with a nontrapping obstacle. In the more
general case, this work contemplates the boundary control of a transmission
problem admitting several zones of transmission. The result is obtained using
the technique developed by David Russell, taking advantage of the local energy
decay for the problem, obtained through the Scattering Theory as used by Vodev,
combined with a powerful trace Theorem due to Tataru.
