In section 2.17.2 there is no
aring å small a, ring
and in section 2.17.3
ã Small a, tilde <!-- is ok -->
ä Small a, tilde <!-- may be Small a, dieresis ... -->
å Small a, dieresis or umlaut <!-- may be Small a, ring -->
Futhermore, section 2.17.3 does not have an entry for the non-breaking
space.
Mike