Horse & Pony Books:
THE CHESTNUT PONY
(COUNTRY LIFE 1939)
ILLUSTRATED BY MYRTLE JERRETT
Reprinted by Country Life in 1941
SUMMARY: The story of a horse called Rodeo who is (surprise surprise)chestnut.
Although not a common book, it can be found without too much trouble on internet bookshops both in the UK and the USA. It does seem hard to find with a dust jacket however.