URLDate
Verified		Extra Software
Requirements
(if any)		Access
Conditions		Notes
http://dx.doi.org/10.1016/0378-3774(91)90026-FDOI Link
http://ac.els-cdn.com/037837749190026F/1-s2.0-0378[...]11/14/2016PDF ReaderItem is within a limited-access website
http://www.sciencedirect.com/science/article/pii/0[...]12/15/2016PDF ReaderItem is within a limited-access website