Gaya APA
obstetri williams edisi 23 vol 2. (2012).
jakarta:
EGC.
Gaya Chicago
obstetri williams edisi 23 vol 2.
ed.23.
jakarta:
EGC,
2012.
Text.
Gaya MLA
obstetri williams edisi 23 vol 2.
ed.23.
jakarta:
EGC,
2012.
Text.
Gaya Turabian
obstetri williams edisi 23 vol 2.
jakarta:
EGC,
2012.
Print.