odoo/addons/crm_partner_assign/res_partner_view.xml

<?xml version="1.0"?>
<openerp>
    <data>
        <record id="view_crm_partner_geo_form" model="ir.ui.view">
            <field name="name">res.partner.geo.inherit</field>
            <field name="model">res.partner</field>
            <field name="type">form</field>
            <field name="inherit_id" ref="base.view_partner_form"/>
            <field name="arch" type="xml">
                <xpath expr="//notebook[last()]" position="inside">
                    <page string="Geo Localization">
                        <field name="partner_weight"/>
                        <label string="" colspan="1"/>
                        <button
                            string="Geo Localize"
                            name="geo_localize"
                            icon="gtk-apply"
                            type="object"/>
                        <newline/>
                        <field name="partner_latitude"/>
                        <field name="partner_longitude"/>
                        <field name="date_localization"/>
                    </page>
                </xpath>
            </field>
        </record>
    </data>
</openerp>