Volume 13, Issue 3, March 2012, Pages 969-974
Volume 13, Issue 1, January 2012, Pages 283-287
Volume 12, Issue 1, January 2011, Pages 203-209
Volume 11, Issue 2, February 2010, Pages 377-381
Volume 9, Issue 2, February 2008, Pages 221-228
Volume 7, Issue 4, April 2006, Pages 509-514
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