Operational General Relativity - Lecture 4

          @misc{ scivideos_PIRSA:17110059,
            doi = {},
            url = {https://pirsa.org/17110059},
            author = {Hardy, Lucien},
            keywords = {Quantum Foundations},
            language = {en},
            title = {Operational General Relativity - Lecture 4},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2017},
            month = {nov},
            note = {PIRSA:17110059 see, \url{https://scivideos.org/index.php/pirsa/17110059}}
          }