H. W. Hubbard
- Design of the retaining walls for the M25 cut and cover tunnel at Bell Common. In: Géotechnique, v. 34, n. 4 (Dezember 1984). (1984):
- M25 North-East Sector: Design of Holmesdale and Bell Common Tunnels. In: Proceedings of the Institution of Civil Engineers, v. 78, n. 4 (August 1985). (1985):