1. Furman, N.H. Anal. Chem. Vol. 22, p. 33, 1950.
2. Analoid Methods of Analysis,“ Folder No. 340 R (reprinted Nov., 1958) issued by Ridsdale and Co., Ltd., Newham Hall, Middlesborough, England, pp. 61–70.
3. Glasstone, S. The Elements of Physical Chemistry (D. Van Nostrand Co., Inc., New York, 1954), 10th ed., pp. 455–457.