Gaya APA
Allen, W, L. (1996).
May 1996: National Geographic VOL.189, NO.5 (May 1996).
Washington D.C:
National Geographic.
Gaya MLA
Allen, William, L..
"May 1996: National Geographic VOL.189, NO.5".
May 1996
Washington D.C:
National Geographic,
1996.
Text.