odoo/addons/sale/sale_wizard.xml

<?xml version="1.0" encoding="utf-8"?>
<openerp>
    <data>
        
        <wizard
			id="wizard_sale_order_make_invoice" 
			keyword="client_action_multi" 
			model="sale.order" 
			name="sale.order.make_invoice" 
			multi="True"
			string="Make invoices"/>
        
        <wizard
			id="wizard_sale_order_line_invoice" 
			keyword="client_action_multi"
			model="sale.order.line" 
			name="sale.order.line.make_invoice" 
			multi="True"
			string="Make invoices"/>
        
    </data>
</openerp>