APA Style
Kurniawan, E, H. (2017).
21 st Century teacher= catatan guru abad 21 (Cet. 1).
Surabaya:
CV. Pustaka Mediaguru.
MLA Style
Kurniawan, Erwin, Hari.
"21 st Century teacher= catatan guru abad 21".
Cet. 1
Surabaya:
CV. Pustaka Mediaguru,
2017.
Text.