30 year anniversary :
Library of Congress Office, Rio de Janeiro, Brazil = 30o. aniversário /
Library of Congress.
APA Citation
Library of Congress. Library of Congress Office, R. de Janeiro., Library of Congress. (1997). 30 year anniversary: Library of Congress Office, Rio de Janeiro, Brazil = 30o. aniversário. Rio de Janeiro, RJ: Library of Congress Office, Rio de Janeiro, Brazil.
MLA Citation
Library of Congress. Library of Congress Office, Rio de Janeiro, and Library of Congress. 30 Year Anniversary: Library of Congress Office, Rio De Janeiro, Brazil = 30o. Aniversário. Rio de Janeiro, RJ: Library of Congress Office, Rio de Janeiro, Brazil, 1997.
Warning: These citations may not always be complete (especially for serials).