http://onlinelibrary.wiley.com/doi/10.1002/stab.200610022/abstract
http://onlinelibrary.wiley.com/doi/10.1002/stab.200610022/abstract
http://onlinelibrary.wiley.com/doi/10.1002/stab.200610022/abstract
http://onlinelibrary.wiley.com/doi/10.1002/stab.200610022/abstract
http://onlinelibrary.wiley.com/doi/10.1002/stab.200610022/abstract