APA

U.S. Citizenship and Immigration Services, . (2012). ���ong b�ao di c� ���en t�� kh��ap n�i tr�en th��e gi��i khi nh��ap t�ich lu�on h�anh di��en l�a c�ong d�an hoa k�y. [Washington, D.C.]: U.S. Citizenship and Immigration Services.

Chicago

U.S. Citizenship and Immigration Services, . 2012. ���ong b�ao di c� ���en t�� kh��ap n�i tr�en th��e gi��i khi nh��ap t�ich lu�on h�anh di��en l�a c�ong d�an hoa k�y. [Washington, D.C.]: U.S. Citizenship and Immigration Services.

Harvard

U.S. Citizenship and Immigration Services, . (2012). ���ong b�ao di c� ���en t�� kh��ap n�i tr�en th��e gi��i khi nh��ap t�ich lu�on h�anh di��en l�a c�ong d�an hoa k�y. [Washington, D.C.]: U.S. Citizenship and Immigration Services.

MLA

U.S. Citizenship and Immigration Services, . ���ong b�ao di c� ���en t�� kh��ap n�i tr�en th��e gi��i khi nh��ap t�ich lu�on h�anh di��en l�a c�ong d�an hoa k�y. [Washington, D.C.]: U.S. Citizenship and Immigration Services. 2012.