Spectral Search for Echoes

          @misc{ scivideos_PIRSA:20020093,
            doi = {10.48660/20020093},
            url = {https://pirsa.org/20020093},
            author = {Holdom, Bob},
            keywords = {Quantum Gravity},
            language = {en},
            title = {Spectral Search for Echoes },
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2020},
            month = {feb},
            note = {PIRSA:20020093 see, \url{https://scivideos.org/pirsa/20020093}}
          }