Gaya APA
maggs, M. (1984).
grolier programmed english course 3 .
united statesof america:
[s.l].Grolier International. Inc.
Gaya MLA
maggs, Margaret.
"grolier programmed english course 3".
united statesof america:
[s.l].Grolier International. Inc,
1984.
Koleksi Elektronik.