1. 1) Barbara Stack: Handbook of Mining and Tunnelling Machinery, (Wiley, 1982), 549-565.
2. 2) H. Imai and S. Yamada: Journal of MMIJ, 114 (1998), 693-698.
3. 3) K. Sato, K. Imamura, T. Kasai and H. Kawaguchi: Tankou-Kikai-Youran, (The Coal Mining Research Center, Tokyo, 1986), 58-61.
4. 4) Japan Tunnelling Assoc.: Tunnelling Technology White Paper, (Japan Tunnelling Assoc., Tokyo, 2006), 5-18 —5-24.
5. 5) Coal Mining division of MMIJ: Tenbou, Journal of MMIJ, (1960-1970).