Gaya APA
Gier, K.
(2013).
Shapphire Blue: Time Travel Trilogy Buku 2
.
Jakarta:
PT. Elex Media Komputindo.
Gaya MLA
Gier, Kerstin.
"Shapphire Blue: Time Travel Trilogy Buku 2".
Jakarta:
PT. Elex Media Komputindo,
2013.
Text.