We thank two anonymous reviewers for their constructive comments and suggestions. The first author would also like to thank the IRIS/CIPR cooperative research project “Integrated Workflow and Realistic Geology,” which is funded by industry partners ConocoPhillips, Eni, Petrobras, Statoil, and Total, as well as the Research Council of Norway (PETROMAKS) for financial support.
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In the literature, the vector with the opposite sign, y −
An exception is in the case that γ = +∞ and ξl = 1. This implies that
One may also let