1. International Labour Organization. C171 - Night Work Convention, 1990 (No. 171). Accessed December 22, 2020. https://www.ilo.org/dyn/normlex/en/f?p=1000:12100:0:NO:P12100_INSTRUMENT_ID,P12100_LANG_CODE:312316,en:NO
2. Ministry of Goverment Legislation. Labor Standards Act Article 56. Updated March 20, 2018. Accessed December 22, 2020. https://www.law.go.kr/LSW/eng/engLsSc.do?menuId=2&query=LABOR%20STANDARDS%20ACT#liBgcolor21
3. Industrial shift systems