Gaya APA
HUMPHREYS, K, K. (1983).
BASIC MATHEMATICS AND COMPUTER TECHNIQUES FOR COAL PREPARATION AND MINING .
USA:
DEKKER.
Gaya MLA
HUMPHREYS, KENNETH, K..
"BASIC MATHEMATICS AND COMPUTER TECHNIQUES FOR COAL PREPARATION AND MINING".
USA:
DEKKER,
1983.
Textbook.