00554nam a2200181Ia 450000500170000000800460001703700100006304000080007304000080008104000080008904100080009704100080010508400080011310000110012124501690013226000090030185600620031020260320201709.0008  262003s9999    xx            000 0 eng d  aEBOOK  aCRL  beng  cCRL  2eng  aeng  qCRL  aDowney 2aA Hierarchy of Turing Degrees: A Transfinite Hierarchy of Lowness Notions in the Computably Enumerable Degrees, Unifying Classes, and Natural Definability (AMS-206)  bIEEE  uhttps://ieeexplore.ieee.org/servlet/opac?bknumber=9452519