How to click this type of webpage button ?

<div id="div_sMenu_text_wimax_auth.php" class="s_text" style="top: 101px;">
<table onclick="if(loading == 1) return;change_page("wimax_auth.php")" onmouseover="change_focus_over("div_sMenu_img_wimax_auth.php")" onmouseout="change_focus_out()" width="120px" height="30px" style="color: rgb(255, 255, 255); cursor: pointer;">
<tbody>
<tr>
<td>Authentication</td>
</tr>
</tbody>
</table>
</div>

I didnt find any clue in google on invoking a click for this type of button
I tried this, it worked for other types of button

For Each element As HtmlElement In WebBrowser1.document.GetElementsByTagName("input")
        If element.GetAttribute("class") = "btn" Then 
            element.InvokeMember("click")
        End If
Next

It's urgent, and thanks in advance