https://www.st-andrews.ac.uk/history/ssne/item.php?id=481
DUWALL, MAURITZ [SSNE 481] - The Scotland, Scandinavia and Northern European Biographical Database
https://arts.st-andrews.ac.uk/history/ssne/item.php?id=4143
DUWALL, HEIDE [SSNE 4143] - The Scotland, Scandinavia and Northern European Biographical Database
https://www.st-andrews.ac.uk/history/ssne/item.php?id=2454
DUWALL, JAKOB [SSNE 2454] - The Scotland, Scandinavia and Northern European Biographical Database
https://www.st-andrews.ac.uk/history/ssne/item.php?id=2444
DUWALL, ALBREKT [SSNE 2444] - The Scotland, Scandinavia and Northern European Biographical Database
https://www.st-andrews.ac.uk/history/ssne/item.php?id=478
DUWALL, AXEL [SSNE 478] - The Scotland, Scandinavia and Northern European Biographical Database