00514nam a22001817a 4500008004100000020001800041040005500059080002200114100002900136245003500165250001200200260004400212300001500256650001400271653001800285942001200303999001700315230322b        |||||||| |||| 00| 0 eng d  a0-914894-36-6  aNational Science LibrarycNational Science Library  aD 681.3:65bM0;M21 aUllman, Jeffrey D 94117  aPrinciples of database systems  a2nd ed.  aLondon: bPitman Publishing Ltd, c1982  avii, 484p.  aDatabases  aNetwork model  2udccBK  c12385d12385