This specific 3D model, "Swimming pool 3D model 10", is an asset made available by "Unknown author".
Can be downloaded at "Unknown platform" by following the link.
The license for this digital asset is "Unknown license".
STL (Stereolithography, filesize: 206 MB), OBJ (OBJ, filesize: 206 MB), DAE (Collada, filesize: 206 MB), DWG (AutoCAD, filesize: 206 MB), DXF (DXF, filesize: 206 MB), FBX (Autodesk FBX, filesize: 206 MB), MAX (Autodesk 3ds Max, filesize: 206 MB), 3DS (3D Studio, filesize: 206 MB), SKP (Sketchup, filesize: 206 MB)