Based on common file-naming conventions, this likely refers to a or a collection of 3D models/assets (often used in architectural visualization or game development) rather than a traditional academic paper. The "250" often signifies the number of items in the collection, and ".rar" is a compressed archive format.
If you are looking for this for a specific project, could you clarify if you need: Download autos and buses 250 rar
A dataset for vehicle recognition or traffic flow analysis? Based on common file-naming conventions, this likely refers
A technical paper that mistakenly uses this filename as a reference? Based on common file-naming conventions
Knowing the of your project will help me track down the right source or a high-quality alternative for you.
Models for software like AutoCAD, 3ds Max, or SketchUp?