tryton/modules/purchase/view/purchase_form.xml

<?xml version="1.0"?>
<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of
this repository contains the full copyright notices and license terms. -->
<form col="6">
    <label name="party"/>
    <field name="party"/>
    <label name="contact"/>
    <field name="contact"/>
    <label name="number"/>
    <field name="number"/>
    <label name="invoice_party"/>
    <field name="invoice_party"/>
    <label name="invoice_address"/>
    <field name="invoice_address" colspan="3"/>

    <label name="description"/>
    <field name="description" colspan="3"/>
    <label name="reference"/>
    <field name="reference"/>
    <notebook colspan="6">
        <page string="Purchase" id="purchase">
            <label name="purchase_date"/>
            <field name="purchase_date"/>
            <label name="payment_term"/>
            <field name="payment_term"/>
            <label name="warehouse"/>
            <field name="warehouse"/>
            <label name="currency"/>
            <field name="currency"/>
            <field name="lines" colspan="4"
                view_ids="purchase.purchase_line_view_tree_sequence"/>
            <group col="2" colspan="2" id="states" yfill="1">
                <label name="invoice_state"/>
                <field name="invoice_state"/>
                <label name="shipment_state"/>
                <field name="shipment_state"/>
                <label name="state"/>
                <field name="state"/>
            </group>
            <group col="2" colspan="2" id="amount" yfill="1">
                <label name="untaxed_amount" xalign="1.0" xexpand="1"/>
                <field name="untaxed_amount" xalign="1.0" xexpand="0"/>
                <label name="tax_amount" xalign="1.0" xexpand="1"/>
                <field name="tax_amount" xalign="1.0" xexpand="0"/>
                <label name="total_amount" xalign="1.0" xexpand="1"/>
                <field name="total_amount" xalign="1.0" xexpand="0"/>
            </group>
        </page>
        <page string="Other Info" id="info">
            <label name="company"/>
            <field name="company"/>
            <label name="origin"/>
            <field name="origin"/>
            <label name="invoice_method"/>
            <field name="invoice_method"/>
            <label name="delivery_date"/>
            <field name="delivery_date"/>
            <label name="quoted_by"/>
            <field name="quoted_by"/>
            <label name="confirmed_by"/>
            <field name="confirmed_by"/>
            <separator name="comment" colspan="4"/>
            <field name="comment" colspan="4"/>
        </page>
    </notebook>
    <group id="links" col="-1" colspan="3">
        <link icon="tryton-shipment-in" name="purchase.act_shipment_form"/>
        <link icon="tryton-account" name="purchase.act_invoice_form"/>
        <link icon="tryton-shipment-out" name="purchase.act_return_form"/>
    </group>
    <group col="-1" colspan="3" id="buttons">
        <button name="cancel" icon="tryton-cancel"/>
        <button name="draft"/>
        <button name="modify_header" icon="tryton-launch"/>
        <button name="quote" icon="tryton-forward"/>
        <button name="handle_invoice_exception" icon="tryton-forward"/>
        <button name="handle_shipment_exception" icon="tryton-forward"/>
        <button name="confirm" icon="tryton-ok"/>
        <button name="process"/>
        <button name="manual_invoice" icon="tryton-forward"/>
    </group>
    <field name="party_lang" invisible="1" colspan="6"/>
</form>