1. C. Bring Friction and Slipping 1964
2. C. Bring Testing of Slipperiness 1982
3. The effect of conditions underfoot on falling and overexertion accidents
4. DIN 51097-1980: Determination of the Slide-Blocking Property of Wet-Loaded Barefoot Areas
5. G. Lees 33 48 Clay Paving Bricks (Proc 1989