Gaya APA
p.rein, D. (1985).
Grolier Advance English Course 1 .
the United States of America:
grolierinternational.
Gaya MLA
p.rein, David.
"Grolier Advance English Course 1".
the United States of America:
grolierinternational,
1985.
Koleksi Elektronik.