In an interesting article that tackles this question Matthew Woodward develops a very simple answer to this question. Indexing links in google is not a complicated process and it should be simple. Keeping in mind this statement this should be one of the quickest posts you should ever read but in here is all you need to know about this question.
The Best Way To Get Backlinks Indexed
- Wait upto 2 weeks for Google to find them naturally
- If they are not indexed, ping each of them which is free to do
- Wait another week
- If the backlinks are still not indexed submit them to OneHourIndexing or Indexification
- Track all of your results
- This process will guarantee your backlinks get indexed
If you want to read more I recommend this link.