Dissertations & ThesesProQuest Dissertations & Theses (PQD&T) is the single, central, authoritative resource for information about doctoral dissertations and master's theses. Contains more than 2 million entries including dissertations published from 1980 forward include 350-word abstracts written by the author. Master's theses published from 1988 forward include 150-word abstracts. UMI offers over 1.8 million titles for purchase in microfilm or paper formats. More than 600,000 are available in native or image PDF formats for immediate free download. Coverage from 1861-present.