cooperative-market/beesdoo_purchase/report/report_purchaseorder.xml

<?xml version="1.0" encoding="utf-8"?>
<odoo>
    <data>
        <template id="report_purchaseorder_document"
                  inherit_id="purchase.report_purchaseorder_document"
                  name="beesdoo purchaseorder">
            <div t-if="o.date_order" position="after">

                <div t-if="o.create_uid.name" class="col-xs-3">
                    <strong>Your Referent:</strong>
                    <div t-field="o.create_uid"
                         t-options='{"widget": "contact", "fields": ["name", "phone", "mobile"], "no_marker": true, "phone_icons": true}'/>
                </div>

            </div>
        </template>
    </data>
</odoo>