SEMI-TRACTORS
It should be noted that the a lot of heavy (and in some cases, medium and even light) trucks of many countries have semi-tractor variants of those vehicles. For most of these, I have only very sketchy details and they are not included here. In a similar vein, I have not been able to find much in the way of civilian semi-tractors (or civilian heavy trucks and equipment in general), and they are not included here. Perhaps in the future...