Murder At the Library of Congress by Margaret Truman

Was there a second diary, beyond the one Columbus kept, describing his voyage to the New World? Leading scholars at the Library of Congress think so, and Annabel Smith, with her pre-Columbian interests, has been commissioned by the library's magazine, Civilization, to write about it.  She is not the only person interested. Word comes through the rare-books black market that a wealthy bibliophile has been offered the second diary: He'd not only pay, he'd almost kill to possess it. Starting her search in the library itself, Annabel soon finds herself competing with an ambitious TV journalist. As both women come closer to finding the hidden documents, other questions creep up. Was the murder of the library's most prominent Hispanic scholar connected to the missing diary? Further research leads them deeper into barely explored corners of the library and closer to having to face their own mortality.