Permissions for resource types

I found this at: opencms-forum.de

How to disable the structured content window from showing up in the explorer

<explorertype name="Author" key="fileicon.Author" icon="xmlcontent.gif" reference="xmlcontent">

                   <newresource page="structurecontent" uri="newresource_xmlcontent.jsp?newresourcetype=Author" order="225" autosetnavigation="false" autosettitle="false"/>
                   <accesscontrol>
                   	<accessentry principal="GROUP.Administrators" permissions="-r-v-w-c"/>
                       <accessentry principal="GROUP.Projectmanagers" permissions="-r-v-w-c"/>
                       <accessentry principal="GROUP.Users" permissions="-r-v-w-c"/>                                          
                   </accesscontrol>
                   <editoptions>
                       <defaultproperties enabled="false" shownavigation="false"/>
                       <contextmenu/>
                   </editoptions>
               </explorertype>