“…The power and limitations of such networks have already been studied in Refs. [ 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 ], however, it is still unclear which useful quantum states can actually be prepared using them. In the most general definition, the parties and the sources can additionally share a global classical random variable, and we say that such networks arise from local operations and shared randomness ( losr ).…”