544 g Gibb, Thomas Robinson Pirie'
Optical methods of chemical analysis* 1*
ed* sixth impression* Hew York, McGraw-Hill
Book Co., 1942.
391 p. ilus.t tablas, diagrs* 21 cm. (In-
ternational chemical series, L. P* Harmett, -
consulting editor)
Bibliograffa al final de los capftulos.