Terminology in coal research

Author:	Thiessen, Reinhardt,
Additional Authors:	Francis, Wilfrid,
Year:	1929
Document Type:	USBM
Issuing Agency:	U.S. Dept. of the Interior, Bureau of Mines,
SUDOC:	C 22.5:446
Series:	Technical paper / United States Department of the Interior, Bureau of Mines ;
Report Number:	446
Subject:	Coal
Link:	https://hdl.handle.net/2027/mdp.39015077315987