+YAZ_EXPORT int odr_external(ODR o, Odr_external **p, int opt);
+
+YAZ_EXPORT int odr_visiblestring(ODR o, char **p, int opt);
+YAZ_EXPORT int odr_graphicstring(ODR o, char **p, int opt);
+YAZ_EXPORT int odr_generalizedtime(ODR o, char **p, int opt);