Gaya APA
Karr, C, J. (1979).
Analytical Methods for Coal and Coal Products Vol. 3 (III) (E-Book) .
United States of America:
Academic Press Inc.
Gaya MLA
Karr, Clarence, Jr.
"Analytical Methods for Coal and Coal Products Vol. 3 (III) (E-Book)".
United States of America:
Academic Press Inc,
1979.
E-book.