APA

Eckel E. C., . (1914). Iron ores. New York: McGraw-Hill Book Company.

Chicago

Eckel E C, . 1914. Iron ores. New York: McGraw-Hill Book Company.

Harvard

Eckel E. C., . (1914). Iron ores. New York: McGraw-Hill Book Company.

MLA

Eckel E C, . Iron ores. New York: McGraw-Hill Book Company. 1914.