Advanced General Relativity - Lecture 20

          @misc{ scivideos_PIRSA:13030029,
            doi = {},
            url = {https://pirsa.org/13030029},
            author = {Sorkin, Rafael},
            keywords = {},
            language = {en},
            title = {Advanced General Relativity - Lecture 20},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2013},
            month = {mar},
            note = {PIRSA:13030029 see, \url{https://scivideos.org/index.php/pirsa/13030029}}
          }