400. That’s an error.

Google cannot redirect you to http://worldcat.org/search?q=difettosi+comedia+di+Giouanni+Briccio+detto+il+Circospetto+nella+Congrega+Taciturni.+All'ill.mo+...+il+signor+duca+di+Vallemutia+giovanni+briccio+pietro+principe+gabrielli+gaspare+servi 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.