By Kaplan
By Health and Safety Executive (HSE)
By Ankie M. M. Hoogvelt
By Tony Butcher
By Martin Field
By Daniel Farnham, Sylvia Horton
By Gini Graham Scott
By Paul Edwards, Sarah Edwards, Linda Rohrbough
By Robert W. McChesney
By Anna Leask, Alan Fyall
By BPP Learning Media
By Paul C. Light
By R. B. Outhwaite
By Robert Whelan, etc.
By Reverend Dr John Wilson
By Grant, David, McLarty, Robert
By Lanon, Tullis, Graham
By Maurice E. Baren
By David Lewis, Malcolm Sargeant, Ben Schwab
By Kathy Daniels, Lynda Macdonald