a.o. ,     Bollini D.. ,     Frabetti P.L. ,     Heiman G.. ,     Baranov S.P. Muon pairs and upper limit for upsilon production by 280 GeV muons. Nucl.Phys. , Vol.199,N1 , с. P.27-35 , 01.1982   a.o. ,     Bollini D.. ,     Baranov S.P. ,     Benvenuti A.C. ,     Bruni G.. ,     Grushin V.F. ,     Komar A.A. ,     Shikanyan A.A. ,     Telyukov E.V. Upper limits on D~ -D~ mixing ang BB production from muon-nucleon scattering. Phys.Lett.B , Vol.158B,N6 , с. P.531-535 , 01.1985