Yes defiantly link exchange can boost you page rank but for that to work effectively the links you get from other sites have to be from " authority sites". For example an authority site may be an extremely popular website that relates 100% to you industry which has a PR of 5 or higher. A link from an authority site is worth 100 links from your average site so to speak so it is better to have quality links pointing back to your site. Another great way to get links is to launch press releases because as time passes that article gets archived and its PR will eventually which at the same time is pointing to your website. Hope this helps.
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