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2. Hillebrand and Lundell,Applied Inorganic Analysis, p. 429 (1955).
3. Scott, W. W.Standard Methods of Chemical Analysis, 5th Ed, p. 1057 (1945).
4. Hillebrand and Lundell,Applied Inorganic Analysis, p. 426 (1955).
5. THE USE OF A SULFATE-HYDROSULFATE BUFFERED SOLUTION FOR THE PRECIPITATION OF ZINC SULFIDE