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https://news.joins.com/article/23338788

http://news.mk.co.kr/newsRead.php?year=2019&no=37159

http://news.heraldcorp.com/view.php?ud=20190114000371

https://dasanzhone.com/press-releases-post/dzs-to-announce-fourth-quarter-and-full-year-2018-financial-results-on-february-28th/

http://news.wowtv.co.kr/NewsCenter/News/Read?articleId=A201901070027&t=NNv

http://www.etnews.com/20190104000266

https://dasanzhone.com/media-center/press-releases/

http://news.mt.co.kr/mtview.php?no=2019010111201212903