/// be the one referenced in the crossref field.
docstring getValueForKey(std::string const & key, Buffer const & buf,
docstring const & before, docstring const & after, docstring const & dialog,
/// be the one referenced in the crossref field.
docstring getValueForKey(std::string const & key, Buffer const & buf,
docstring const & before, docstring const & after, docstring const & dialog,