Kim, S-M
Kim, H
Yun, M R
Kang, H N
Pyo, K-H
Park, H J
Lee, J M
Choi, H M
Ellinghaus, P
Ocker, M
Paik, S
Kim, H R
Cho, B C
Article History
Received: 21 January 2016
Revised: 30 May 2016
Accepted: 6 June 2016
First Online: 18 July 2016
Competing interests
: The authors declare no conflict of interest.