Volume 6, Issue 4, October 2012, Pages 933-944
A. López-Piñeiro; A. Albarrán; D. Cabrera; D. Peña; D. Becerra
Volume 4, Issue 4, November 2010, Pages 807-816
C.N. Owabor; S.E. Ogbeide; A.A. Susu
Volume 2, Issue 1, January 2008, Pages 23-26