Error - DOI Naming Authority [proc] Not Found

The DOI you requested --

proc/2007-135-04/S0002-9939-06-08558-3/S0002-9939-06-08558-3.pdf

-- cannot be found in the Handle System.

Possible reasons for the error are:

• the DOI has not been created
• the DOI is cited incorrectly in your source
• the DOI does not resolve due to a system problem

If you believe you have requested a DOI that should be found, you may report this error by filling out the form below: