11. The additive group of integers has 1 as a generating set . 12. Their product range include diesel engines, agricultural pumpsets and generating sets . 13. Instead of heavy fuel oil the auxiliary generating sets run on marine diesel oil. 14. If " R " is a finitely-generated, there may exist no minimal generating set . 15. In 1972, some of the station's older generating sets were taken out of service. 16. By 1972, the CEGB had installed 42 Olympus generating sets . 17. It powered the Bristol Britannia airliner, small naval patrol craft, hovercraft and electrical generating sets . 18. Firstly, a sequence of abstract expressions requires less memory than terms over the generating set . 19. The Tema power station was commissioned in 1956 with a 3 x diesel generating set . 20. Shipboard power was generated by two auxiliary generating sets .