| `Fact -> Xml.xml_empty "flavour" [None, "value", "fact"]
| `Lemma -> Xml.xml_empty "flavour" [None, "value", "lemma"]
| `Remark -> Xml.xml_empty "flavour" [None, "value", "remark"]
| `Theorem -> Xml.xml_empty "flavour" [None, "value", "theorem"]
| `Variant -> Xml.xml_empty "flavour" [None, "value", "variant"]
| `Fact -> Xml.xml_empty "flavour" [None, "value", "fact"]
| `Lemma -> Xml.xml_empty "flavour" [None, "value", "lemma"]
| `Remark -> Xml.xml_empty "flavour" [None, "value", "remark"]
| `Theorem -> Xml.xml_empty "flavour" [None, "value", "theorem"]
| `Variant -> Xml.xml_empty "flavour" [None, "value", "variant"]