| Year | 1987 |
| Date | 06-Feb |
| Volume | 158 |
| Issue | 3,794 |
| Page | 166 |
| Category | Locomotive |
| Part | |
| Title | Correspondence and Criticisms Concerning the Cleminson and Heywood Systems |
| Author | Mark Smithers |
| Notes | Prior claims of origination, behaviour of the Cleminson system, what conclusions can be drawn, the Duffield Bank Railway |