Is the biometric data used in voter identification at polling stations?

Viet Nam Electoral Law

Chapter IV LISTS OF VOTERS

Article 24. The voters lists shall be drawn up by the commune/ward/township People’s Committee according to the electorates.

The voters list in a People’s Armed Forces unit shall be drawn up by the unit’s command according to the electorate. A military personnel who has his/her permanent residence registration in a locality near his/her encampment area may be granted a certificate by the unit command so that his/her name shall be included in the voters list and he/she shall vote in such locality. When issuing the certificate, the unit commander must write down in the list next to his/her name 'Vote in the place of residence.'

Source: http://aceproject.org/ero-en/regions/asia/VN/vietnam-law-of-1997-on-election-of-deputies-to-the/view