Gaya APA
Letter writing. (1971).
tempaterbit:
penerbit.
Gaya Chicago
Letter writing.
Edisi.
tempaterbit:
penerbit,
1971.
Text.
Gaya MLA
Letter writing.
Edisi.
tempaterbit:
penerbit,
1971.
Text.
Gaya Turabian
Letter writing.
tempaterbit:
penerbit,
1971.
Print.