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https://ja.hideki.hclippr.com/2015/05/11/%e6%97%a5%e6%9c%ac%e3%81%a7%e3%81%aet-mobile%e3%83%ad%e3%83%bc%e3%83%9f%e3%83%b3%e3%82%b0%e4%bd%93%e9%a8%93%e8%ab%87/
日本でのT-mobileローミング体験談