545.8 Bol C Boltz, David Ferdinand, 1918- ed. Colorimetric determination of nonmetals. New York, Interscience Pub., 1958. 372 p. ilus., diagrs. 24 cm. (Chemical analysis, a series of monographs on analytical chemistry and its applications, t. 7) BibliografĂ­a al final de los capĂ­tulos.