Correct usage of the copyright tag

Hi,

what is the "correct" way of using the copyright tag for multiple years?

I used to use the following:

<copyright>
            <year>2007</year>
            <year>2008</year>
            <year>2009</year>
            <year>2010</year>
            <year>2011</year>
            <year>2012</year>
            <year>2013</year>
            <year>2014</year>
            <year>2015</year>
            <holder>Someone</holder>
</copyright>

But that results in the PDF output to:

Copyright © 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015 Someone

Should I only write the following?

<copyright>
            <year>2007 - 2015</year>
            <holder>Someone</holder>
</copyright>

Best regards, Lars