Statistical abstract of the United States, 2011 : the National data book / U.S. Depart. of Commerce Economics a. Statistics administration U.S. Census Bureau. - 130th ed.. - Washington : National Bibliogr. of U.S. Government publ., 2010. - xviii, 1010 p. : tab. ; 24 cm.см.. - (Statab ; 11, ISSN 0081-4741). - ISBN 978-0-16-086681-4[MFN: 29227]