This word list was created using Viet39K.txt found in the vn_words.zip
package which can be downloaded from
http://www.informatik.uni-leipzig.de/~duc/software/misc/wordlist.html

On that page Ho Ngoc Duc included the notice:

  The word list is distributed under GNU General Public License. If you
  modify it, please send me the modifications.

The vi_VN.aff rules were improved by Ivan Garcia - capiscuas@gmail.com (Sept 2007)
More Info here: http://code.google.com/p/hunspell-spellcheck-vi/