From: Middelfontein
This Prisoner of War record for Willem Johannes Joubert was transcribed record from various documents held at the National Archives, South Africa, including arrest and shipping information from newspaper sources like De Zuid-Afrikaan.
https://www.gendatabase.com/boer-war-prisoner-record.php?q=13118&r=Willem Johannes&s=Joubert&ref=
This set of Prisoner of War documents can be accessed online via the FamilySearch.org project by Clicking Here.