Testing QED with positronium state

          @misc{ scivideos_PIRSA:14080038,
            doi = {10.48660/14080038},
            url = {https://pirsa.org/14080038},
            author = {Penin, Alexander},
            keywords = {Particle Physics},
            language = {en},
            title = {Testing QED with positronium state},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2014},
            month = {aug},
            note = {PIRSA:14080038 see, \url{https://scivideos.org/pirsa/14080038}}
          }