If you are looking to increase your Google Page Rank, you need to do Quality link building. Quality Link Building is nothing but building quality dofollow back links from higher PR sources, especially from those niche relative authority sources.
Having your link on those websites which have more PR than yours would do good, but PR gets divided among the number of links over there. So look outfor those websites which are having a Good Google PR and less outbound links (both internal and external).
Some ways that you can get good Quality Links with Search engine optimisation
Article submission
Blog Commenting (Do Follow Blogs)
Forum posting
Classified ads
Press releases
Link Exchange to relevant sites
Social bookmarking (Sites like HubPage & squidoo are popular)
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