COLORIMETRIC DETERMINATION OF MICROGRAM QUANTITIES OF COBALT WITH p-NITROPHENYL-HYDRAZONE OF DIACETYLMONOXIME
HU HSI-HUA, LEU YU-CHENG, SOONG HSUEH-TZE, CHU PING-TSING
Acta Chimica Sinica . 1958, (3): 255 -257 .