Additional review comments.

chapters/synchronous.tex

@@ -126,7 +126,7 @@ \section{Rationale for Clocked Semantics}\label{rationale-for-clocked-semantics}
   in well-defined ways when needed.
 \item
   Fewer initial conditions are needed, as only a subset of clocked
-  variables need initial conditions -- the clocked state variables \cref{clocked-state-variables}.
+  variables need initial conditions -- the clocked state variables (see \cref{clocked-state-variables}).
   For a standard when-clause all variables
   assigned in a when-clause must have an initial value
   because they might be used, before they are assigned a value the first