http://www.w3.org/1999/xhtml
attributeGroup events

Documentation

      attributes for common UI events
      onclick     a pointer button was clicked
      ondblclick  a pointer button was double clicked
      onmousedown a pointer button was pressed down
      onmouseup   a pointer button was released
      onmousemove a pointer was moved onto the element
      onmouseout  a pointer was moved away from the element
      onkeypress  a key was pressed and released
      onkeydown   a key was pressed down
      onkeyup     a key was released
      

Source

<xs:attributeGroup name="events">
  <xs:attribute name="onclick" type="Script"/>
  <xs:attribute name="ondblclick" type="Script"/>
  <xs:attribute name="onmousedown" type="Script"/>
  <xs:attribute name="onmouseup" type="Script"/>
  <xs:attribute name="onmouseover" type="Script"/>
  <xs:attribute name="onmousemove" type="Script"/>
  <xs:attribute name="onmouseout" type="Script"/>
  <xs:attribute name="onkeypress" type="Script"/>
  <xs:attribute name="onkeydown" type="Script"/>
  <xs:attribute name="onkeyup" type="Script"/>
</xs:attributeGroup>