custom_cemobo/custom_cemobo.xml

<?xml version="1.0" encoding="UTF-8"?>
<openerp>
	<data>
    <record id="view_voucher_tree_cemobo" model="ir.ui.view">
			<field name="name">view_voucher_tree_cemobo</field>
			<field name="model">account.voucher</field>
			<field name="inherit_id" ref="account_voucher.view_voucher_tree"/>
			<field name="arch" type="xml">
				<!-- tree -->
				<tree position="attributes">
					<attribute name="create">0</attribute>
				</tree>
			</field>
		</record>
  </data>
</openerp>