Assets path format?

I’m trying to understand an asset path string format.
For example, the function LoadObject<T>(...) seems to work just fine with all of the following asset path strings:

- "StaticMesh'/Game/Environment/Props/SM_SomeMesh.SM_SomeMesh'"
- "/Game/Environment/Props/SM_SomeMesh.SM_SomeMesh"
- "StaticMesh'/Game/Environment/Props/SM_SomeMesh"

What is the correct asset path string format and is there some official docs for this?