How to link a resource file to jsp?

I have the following structure in my java webapp

-- main
   -- java
   -- resources
      -- lib
         -- css
            -- style.css
   -- webapp
      -- WEB-INF
         -- web.xml
      --index.jsp

How can I link the style.css to my index jsp?

<link rel="stylesheet" href="???">

What should be here?

Thanks in advance