additionalInfo on dataset tag

but not an official namespace

inst/extdata/mappings/geometa_mapping.csv

@@ -15,7 +15,7 @@ $identificationInfo*/ISODataIdentification$citation/ISOCitation$title,$title,$da
 $identificationInfo*/ISODataIdentification$citation/ISOCitation$alternateTitle,$title_short_name,$dataset/$title,ok,?,?,
 $identificationInfo*/ISODataIdentification$citation/ISOCitation$date*/ISODate$date[$dateType/ISODateType$value=creation|item=1],$date_created,,validation issue,?,?,- catch errors when ambiguous values are retrieved from source
 $identificationInfo*/ISODataIdentification$citation/ISOCitation$date*/ISODate$date[$dateType/ISODateType$value=publication|item=1],$date_issued,$dataset/$pubDate,validation issue,ok,ok,- catch errors when ambiguous values are retrieved from source
-$identificationInfo*/ISODataIdentification$supplementalInformation,$comment,additionalInfo,ok,?,?,
+$identificationInfo*/ISODataIdentification$supplementalInformation,$comment,$dataset/$additionalInfo,ok,?,?,
 $identificationInfo*/ISODataIdentification$abstract,$summary,$dataset/$abstract/$para,ok,ok,ok,
 $identificationInfo*/ISODataIdentification$purpose,,$dataset/$purpose,?,ok,ok,
 $identificationInfo*/ISODataIdentification$credit,$acknowledgment,,ok,?,?,