Gaya APA
lane, H, U, . (1981).
Thew World Almanac&Book Of Facts 1981 (1).
Neww York:
NEWS PAPER ENTERRISE ASSOCIATONIC.
Gaya MLA
lane, Hana, Umlauf, .
"Thew World Almanac&Book Of Facts 1981".
1
Neww York:
NEWS PAPER ENTERRISE ASSOCIATONIC,
1981.
Buku.