The OP of the duplicate question needs further clarifications after reading the answers in the original question and he said so in the comments before the question was closed.
Also you'll notice that the accepted answer to the original question is just a link and that, I believe, does not qualify as answer by MSE's standards.
This question should be reopened because:
- The original question doesn't have an acceptable answer, (for it is a link).
- The OP of the duplicate question needs clarification.
I mentioned this in a comment in the duplicate question before the it was closed, but it was deleted.
Edit: and the link forwards to an article which isn't even free.