  We analyze the decay modes $B^0 \to D^{*-} D^0 K^+$ and $B^0 \to D^{*-}
D^{*0} K^+$ and, using the available experimental data, we find bounds for the
constants g and h describing the strong coupling of heavy mesons to light
pseudoscalar mesons. Both the decay channels are dominated by broad L=1 charm
resonances; the dominance is effective also in $B^0 \to D^{-} D^0 K^+$ and $B^0
\to D^{-} D^{*0} K^+$.
