Introduction
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PII: S1071-9091(09)00070-9
doi:10.1016/j.spen.2009.10.001
© 2009 Published by Elsevier Inc.
PII: S1071-9091(09)00070-9
doi:10.1016/j.spen.2009.10.001
© 2009 Published by Elsevier Inc.