400. That’s an error.

Google cannot redirect you to http://worldcat.org/search?q=Conciliator+controversiarum,+quae+inter+philosophos+et+medicos+versantur,Petro+Abano+...+auctore.+Libellus+venenis,+eodem+auctore.+Petri+Carrarij+Quaestio+venenis+ad+terminum.+Symphoriani+Champerij+Lugdunensis+Conciliatorem+cribrationes+..+pietro+:+d'abano 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.