Gaya APA
Scientific Event Alert Network (SEAN) Bulletin Volume 12, No. 4, April 30, 1987. ().
Washington:
Smithsonian Istitution.
Gaya MLA
Scientific Event Alert Network (SEAN) Bulletin Volume 12, No. 4, April 30, 1987.
.
Washington:
Smithsonian Istitution,
.
.