Gaya APA
Think positive. (2011).
Solo:
Mutiara Sumber Widya.
Gaya Chicago
Think positive.
cet.2.
Solo:
Mutiara Sumber Widya,
2011.
NONFIKSI.
Gaya MLA
Think positive.
cet.2.
Solo:
Mutiara Sumber Widya,
2011.
NONFIKSI.
Gaya Turabian
Think positive.
Solo:
Mutiara Sumber Widya,
2011.
NONFIKSI.