Foto: repro majalah Penelitian Sedjarah, Juni 1962.
Sources:
https://web.archive.org/web/20180402175505/http://historia.id/img/foto_berita/x152141002_Sejarah-Indonesia.jpg.pagespeed.ic.0sc-xLk1Ov.jpg
https://web.archive.org/web/20180401225128/http://historia.id/budaya/menggagas-aksara-kesatuan