Stockholm, Sweden.
The following is directly taken from the paper’s abstract section:
Since being introduced in the book ”The C Programming Language”, Hello World has become the typical way of how people are introduced to the world of programming. We observe that the classical approach is conservative, all characters are displayed solely through one programming language. In this paper, we propose an improved version which enables the execution to transpire through multiple languages.
Github repository of the reference implementation
The full paper can be found here.