Gaya APA
Bulletin of the Global Volcanism Network Volume 16, No. 4, April 30, 1991
.
().
Washington:
Smithsonian Istitution.
Gaya MLA
Bulletin of the Global Volcanism Network Volume 16, No. 4, April 30, 1991
.
.
Washington:
Smithsonian Istitution,
.
.