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geonames.usgs.gov/pls/gnispublic/f?p=gnispq:3:::NO::P3_FID:1565841
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geonames.usgs.gov/pls/gnispublic/f?p=gnispq:3:::NO::P3_FID:1583314
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en.wikipedia.org/wiki/Greenfield,_Wisconsin (16 Aug 2010)
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en.wikipedia.org/wiki/Greenfield,_Milwaukee_County,_Wisconsin