Chesler, M, JCT Chen, and RP Kraig.  1994.  Determination of extracellular bicarbonate and carbon dioxide concentrations in brain slices using carbonate and pH-selective microelectrodes. J. Neuro. Meth. 53:129-136.

MacInnes, DA and D Belcher. 1935.  The Thermodynamic ionization constants of carbonic acid at 38 degrees from electromotive force measurements. J. Am. Chem. Soc. 57:1683-1685.

Wietasch, K and RP Kraig.  1991. Carbonic acid buffer species measured in real time with an intracellular microelectrode array.  Am. J. Physiol. 261:R760-R765.