Terms sourced from: 10.1351/pac200880010059

"Further conventions for NMR shielding and chemical shifts (IUPAC Recommendations 2008)", Harris, R.K.;Becker, E.D.;Cabral De Menezes, S.M.;Granger, P.;Hoffman, R.E.;Zilm, K.W., Pure and Applied Chemistry 2008, 80(1), 59