Terms sourced from: http://iupac.org/publications/pac/74/11/2169/

"Measurement of pH. Definition, standards, and procedures (IUPAC Recommendations 2002)", Buck, R.P.;Rondinini, S.;Covington, A.K.;Baucke, F.G.K.;Brett, C.M.A.;Camoes, M.F.;Milton, M.J.T.;Mussini, T.;Naumann, R.;Pratt, K.W.;Spitzer, P.;Wilson, G.S., Pure And Applied Chemistry 2002, 74(11), 2169

pH