Measurement of $R$ between 1.84 and 3.05 GeV at the KEDR detector
  Using the KEDR detector at the VEPP-4M $e^+e^-$ collider, we have determined the values of $R$ at thirteen points of the center-of-mass energy between 1.84 and 3.05 GeV. The achieved accuracy is about or better than $3.9\%$ at most of the energy points with a systematic uncertainty less than $2.4\%$. 
V.V. Anashin, V.M. Aulchenko, E.M. Baldin, A.K. Barladyan, A.Yu.   Barnyakov, M.Yu. Barnyakov, S.E. Baru, I.Yu. Basok, A.M. ...
hep-ex