| Number | Date | Country | Kind |
|---|---|---|---|
| 3824522 | Jul 1988 | DEX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 2803444 | Potts | Aug 1957 | |
| 4073151 | Harmsma | Feb 1978 | |
| 4892446 | Rachel | Jan 1990 |
| Number | Date | Country |
|---|---|---|
| 2055113 | May 1972 | DEX |
| 2229154 | Aug 1974 | DEX |
| 2212686 | Jul 1978 | DEX |
| 2700798 | Sep 1980 | DEX |
| 3110854 | Jan 1983 | DEX |
| 3111875 | Aug 1987 | DEX |
| 1079172 | Aug 1967 | GBX |
| Entry |
|---|
| Jacobi: Automatisierung des Strebausbaus zur besseren Pflege des Hangenden, (1965), Gluckauf, p. 862. |