No white-space

        <a href="http://validator.w3.org/check/referer"><img
        style="border:0px" src="http://www.w3.org/Icons/valid-xhtml11" alt="Valid XHTML 1.1!" /></a>
        <a href="http://jigsaw.w3.org/css-validator/"
        ><img  style="border:0px" src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!" /
        ></a>
        

Result:

"formatting" white-space

        <a href="http://validator.w3.org/check/referer"><img
        src="http://www.w3.org/Icons/valid-xhtml11" style="border:0px" alt="Valid XHTML 1.1!" /></a>
        <a href="http://jigsaw.w3.org/css-validator/">
        <img  style="border:0px" src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!" />
        </a>
        

Result: