Cita APA

Helrich, K. (1990). Official methods of analysis of the association of official analytical chemists. v. 1 (15. ed.). Virginia: Association of Official Analytical Chemists.

Citación estilo Chicago

Helrich, Kenneth. Official Methods of Analysis of the Association of Official Analytical Chemists. V. 1. 15. ed. Virginia: Association of Official Analytical Chemists, 1990.

Cita MLA

Helrich, Kenneth. Official Methods of Analysis of the Association of Official Analytical Chemists. V. 1. 15. ed. Virginia: Association of Official Analytical Chemists, 1990.