Volume 13, Issue 3, March 2012, Pages 827-831
Volume 12, Issue 12, December 2011, Pages 3313-3318
Volume 12, Issue 11, November 2011, Pages 2939-2942
Volume 12, Issue 7, July 2011, Pages 1739-1743
Volume 11, Issue 4, April 2010, Pages 1059-1062
Volume 9, Issue 4, April 2008, Pages 663-670