W. Pickhardt

Trace elements in minerals of German bituminous coals

W. Pickhardt, 1989 .

Determination of Total Carbon in Organic Materials by Wet-Dry Combustion Method

A. Oemler, J. Mitchell, W. Pickhardt, 1955 .

Microdetermination of Carbon and Hydrogen in Pyrophoric and Hygroscopic Organic Compounds

L. Safranski, J. Mitchell, W. Pickhardt, 1958 .