APA (7th ed.) Citation

Helrich, K. (1990). Official methods of analysis of the Association of Official Analytical Chemists (15th edition.). Association of Official Analytical Chemists.

Chicago Style (17th ed.) Citation

Helrich, Kenneth. Official Methods of Analysis of the Association of Official Analytical Chemists. 15th edition. Arlington, VI: Association of Official Analytical Chemists, 1990.

MLA (8th ed.) Citation

Helrich, Kenneth. Official Methods of Analysis of the Association of Official Analytical Chemists. 15th edition. Association of Official Analytical Chemists, 1990.

Warning: These citations may not always be 100% accurate.