Gaya APA
Rubin, Gretchen. (2019).
The Happiness Project .
USA:
Harper.
Gaya Chicago
Rubin, Gretchen.
The Happiness Project.
USA:
Harper,
2019.
Text.
Gaya MLA
Rubin, Gretchen.
The Happiness Project.
USA:
Harper,
2019.
Text.
Gaya Turabian
Rubin, Gretchen.
The Happiness Project.
USA:
Harper,
2019.
Print.