Gaya APA
NIEBEL, B, W., FREIVALDS, A. (2014).
Niebel's Methods, Standards, and Work Design (Thirteenth Edition).
Singapura:
McGraw Hill.
Gaya MLA
NIEBEL, Benjamin, W.., FREIVALDS, Andris.
"Niebel's Methods, Standards, and Work Design".
Thirteenth Edition
Singapura:
McGraw Hill,
2014.
Text.