Add css ,js in xml in magento

<reference name="head">
                <action method="addCss">
                    <stylesheet>css/pagination.css</stylesheet>
                </action>

<action method="addCss"><stylesheet>directory/file.css</stylesheet></action>

<action method="addItem"><type>skin_js</type><name>js/myjavascript.js</name></action>

            </reference>