Citação norma APA

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

Citação norma Chicago

Helrich, Kenneth. Official Methods of Analysis of the Association of Official Analytical Chemists. 15a. ed. Arlington: Association of Official Analytical Chemists, 1990.

Citação norma MLA

Helrich, Kenneth. Official Methods of Analysis of the Association of Official Analytical Chemists. 15a. ed. Association of Official Analytical Chemists, 1990.

Nota: a formatação da citação pode não corresponder 100% ao definido pela respectiva norma.