Links:
[1] https://www.digi-sign.com/digi-ca/code%20signing
[2] https://www.digi-sign.com/taxonomy/term/83
[3] https://www.digi-sign.com/digi-ca/two%20factor%20authentification
[4] https://www.digi-sign.com/downloads/download.php?id=digi-ca-pdf
[5] https://www.digi-sign.com/old/two%20factor%20authentication
[6] https://www.digi-sign.com/digi-ca/two%20factor%20authentication