CONFORMATION OF THE PIPERIDINE RING IN ISOMERIC 1,2,5-TRIMETHYL-4-PHENYL(TRIORGANOSILYL)PIPERIDIN-4-OLS FROM THE PMR SPECTRA ArticleFomichev A.A., Golovtsov N.I., Rezakov V.A., Varlamov A.V., Prostakov M.S.Chemistry of Heterocyclic Compounds. Vol. 22. 1986. P.. 1208-1213