☆少年野球に携わるに当たって、非常に興味深い記事です☆
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https://nenjyu-mukyu.com/2018/05/18/%e5%b0%91%e5%b9%b4%e9%87%8e%e7%90%83%e3%80%80%ef%bc%98x%ef%bc%98%ef%bc%8b%ef%bc%94x%ef%bc%99%ef%bc%9d%ef%bc%91%ef%bc%90%ef%bc%90%e3%81%ae%e6%b3%95%e5%89%87/
