Poetry Books for Autistic Kids

My nine year old likes poetry now and always has. 
He made up his first poem before he was two.
He particularly likes rhymes.
The predictability of a pattern like that may really appeal
to a child on the spectrum.
He sometimes rhymes whatever he says when he is upset
to express his sadness or frustration.
Also, his attention to word and syllable count make him highly aware of poetic structure.

When he was a baby and toddler I could read him poems:
When We Very Young/Milne
Now We Are Six/Milne
Animals, Animals/ illustrated by Carle
Mother Goose/ illustrated by Wells
But by the time he was five he usually objected to my reading the poetry
(it was about the time he wouldn't let me sing to him anymore).
He wants to read it to himself now and will read anything that rhymes, like
Marmion by Sir Walter Scott last year
-heavy going for an eight year old.
I am not recommending it.
He likes the Silversteins,
Where the Sidewalk Ends
A Light in the Attic
but of course the absurdities sometimes cause problems. He likes to change and twist words,
but he also wants to know exactly what everything means-even nonsense words or concepts.
And there is always the danger of perserveration. Currently he is driving us mildly batty
with this:
An eyeball for an eye,
a tooth for a tooth,
a smile for a mouth
that goes north and south.
The Christian Mother Goose also caused problems because
the variants threatened to unseat the standards.
 I want him to have nursery rhymes in common with others.
So what do I recommend? All the baby/toddler stuff I mentioned, and for the older kids,
the ones he's reading now:
Bing Bang Boing/Florian (Harcourt Brace)
Dinothesaurus/Florian (atheneum)
Beastly Feasts!/Forbes (Overlook Duckworth)
A Bundle of Beasts/Hooper (Houghton Mifflin)
A World of Wonders/Lewis (Dial)
There once was a boy, very smart
who struggled to make social art.
He found he could rhyme,
almost all of the time,
and do it with feeling and heart.
-Spectrum Mom