If you are having trouble getting Google to correct your business information in the Google search results or on your Google+ Local page, you should watch this video by David Mihm.
In the video David describes how Google collects information about your business. One of the most important things he points out is that as the business owner, you are only one of many sources where Google gets information about your business.
Here is the direct link to his post on SEOMoz, including the transcript of the video: How Business Listings are Made.
In the video, David mentions this post from Mike Blumenthal: Google’s Business Listing Cluster.
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