Nmm_ocaml : Exml_utils.xml_list_of_ts_authors

let xml_list_of_ts_authors_opt (authors_opt : ts_authors option) : Xml.xml list =
        match authors_opt with
        |None -> []
        |Some (Cs_authors (author_list : ts_author list)) -> 
                [Xml.Element ("authors",[],List.map xml_of_ts_author author_list)]