Gaya APA
Welcher, F, J. (1963).
Standard Methods of Chemical Analysis 6th Edition Volume ll Part A (6).
New York:
Robert E. Krieger Publishing Company.
Gaya MLA
Welcher, Frank, J..
"Standard Methods of Chemical Analysis 6th Edition Volume ll Part A".
6
New York:
Robert E. Krieger Publishing Company,
1963.
Text.