Gaya APA
Norman, V, P., Hery, .
(2011).
Kekuatan faktor plus (power of plus factor)
.
Gorontalo:
CINTABUKU.
Gaya MLA
Norman, Vincent, Peale,., Hery, .
"Kekuatan faktor plus (power of plus factor)".
Gorontalo:
CINTABUKU,
2011.
Text.