http://www.ddaily.co.kr/news/article/?no=183916

http://www.thebell.co.kr/free/content/ArticleView.asp?key=201907230100044750002802&svccode=00&page=1&sort=thebell_check_time

http://www.newstomato.com/ReadNews.aspx?no=909164

http://news.mk.co.kr/v2/economy/view.php?year=2019&no=540613

https://investor-dzsi.com/news/q219-results/

https://www.hankyung.com/finance/article/201907088120M

http://www.nspna.com/news/?mode=view&newsid=369091

https://www.biotcanada.ca/features/extending-fibers-reach/

http://www.newsis.com/view/?id=NISX20190624_0000689410&cID=10401&pID=10400

http://www.fnnews.com/news/201906190807119631