| Year | 1926 |
| Date | 25-Nov |
| Volume | 55 |
| Issue | 1,333 |
| Page | 511 |
| Category | Electrical |
| Part | |
| Title | The Fundamental Principles of the Strowger Automatic Telephone System |
| Author | H.H.Harrison |
| Notes | Arrangement of switches, automatically rotating pre-selwector switch, rotary dial plate of automatic telphone, method of using, explanatory sketch of switch mechanism, connector or final selector with controlling relay group |