http://www.bart.gov/news/articles/2016/news20160415 [4]
http://www.citylab.com/commute/2016/04/in-san-francisco-hog-a-train-seat... [5]
Links
[1] http://www.sdi.re.kr/%23
[2] http://facebook.com/sharer.php?u=http%3A%2F%2Fwww.sdi.re.kr%2Fnode%2F55155&t=%EB%8F%84%EC%8B%9C%EC%B2%A0%EB%8F%84%2C%201%EB%AA%85%EC%9D%B4%201%EC%A2%8C%EC%84%9D%20%EC%9D%B4%EC%83%81%20%EC%A0%90%EC%9C%A0%20%EB%95%90%20%EA%B3%BC%ED%83%9C%EB%A3%8C%20%28%EB%AF%B8%EA%B5%AD%20%EC%83%8C%ED%94%84%EB%9E%80%EC%8B%9C%EC%8A%A4%EC%BD%94%E5%B8%82%29
[3] http://twitter.com/intent/tweet?url=http%3A%2F%2Fwww.sdi.re.kr%2Fnode%2F55155&text=%EB%8F%84%EC%8B%9C%EC%B2%A0%EB%8F%84%2C%201%EB%AA%85%EC%9D%B4%201%EC%A2%8C%EC%84%9D%20%EC%9D%B4%EC%83%81%20%EC%A0%90%EC%9C%A0%20%EB%95%90%20%EA%B3%BC%ED%83%9C%EB%A3%8C%20%28%EB%AF%B8%EA%B5%AD%20%EC%83%8C%ED%94%84%EB%9E%80%EC%8B%9C%EC%8A%A4%EC%BD%94%E5%B8%82%29
[4] http://www.bart.gov/news/articles/2016/news20160415
[5] http://www.citylab.com/commute/2016/04/in-san-francisco-hog-a-train-seat-and-get-a-100-ticket/478587/
[6] http://www.sdi.re.kr/world_trends