400. That’s an error.

Google cannot redirect you to http://worldcat.org/search?q=Le livre l'agriculture. Tr. par J.-J. Clément-Mullet yaḥyà b. muḥammad ibn al-ʻawwâm because the request was invalid.

This might be because the link was created a long time ago. Try your search again on Google. That’s all we know.