Volume 8, Issue 3, March 2007, Pages 417-421
Volume 7, Issue 4, April 2006, Pages 547-555
Volume 7, Issue 3, March 2006, Pages 423-426
Volume 5, Issue 3, March 2004, Pages 273-278
Volume 5, Issue 2, February 2004, Pages 226-228
Volume 4, Issue 3, March 2003, Pages 203-208
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