Here is a case from federalevidence.com:
Supervisor expert testified about his role in the peer review process; passing reference to the testing chemist’s conclusion did not violate the Confrontation Clause; circuit also distinguishes Melendez-Diaz v. Massachusetts, 557 U.S. __, 129 S.Ct. 2527 (2009), in United States v. Turner," _ F.3d _ (7th Cir. Jan. 12, 2010) (No. 08-3109)
A recent Seventh Circuit case revisits the issue of expert testimony which refers to the analysis of another expert. Is the Confrontation Clause violated when a supervisor testifies about the peer review process, his role in confirming reviewing the test results, and the initial results of another chemist? On the fact of the case, the circuit concluded there was no constitutional violation.