As more and more monographs also become Open Access, our colleagues in the Bodleian Library are cataloguing those so they can be found and accessed via SOLO.
“brill online books and journals” “open access”
You can then use the facets on the side to explore which subjects are covered.
Look out for more Open Access monographs. They are freely available and, now that they are integrated into SOLO, should also be discoverable in addition to our purchased and Legal Deposit collections.