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 a.o. , Baranov S.P. , Grushin V.F. , Komar A.A. , Telyukov E.V. The contribution from hadronic showers production and decay to multimuon events in deep inelastic "mu"N scattering. Preprint LPI , N36 , с. 13 c. , 01.1986