From: Elandsfontein
This Prisoner of War record for Barend Christiaan Greyling 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=17809&r=Barend Christiaan&s=Greyling&ref=
This set of Prisoner of War documents can be accessed online via the FamilySearch.org project by Clicking Here.