404. That’s an error.
The requested URL /url?sa=U&q=http://www.springerlink.com/index/E42XJ1FGLT1M0V2N.pdf was not found on this server. That’s all we know.
/url?sa=U&q=http://www.springerlink.com/index/E42XJ1FGLT1M0V2N.pdf