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geonames.usgs.gov/pls/gnispublic/f?p=gnispq:3:::NO::P3_FID:252620
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en.wikipedia.org/wiki/Avon,_Contra_Costa_County,_California (25 Aug 2010)
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en.wikipedia.org/wiki/Avon,_California (17 Jun 2010)
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geonames.usgs.gov/pls/gnispublic/f?p=gnispq:3:::NO::P3_FID:2411658