00318nam a2200109 a 450000500170000002000180001708200130003510000160004824500730006426000460013730000250018320251203111357.0  a9788184082388  a020bRAT  aRatzan, lee  aUnderstanding information systemsbwhat they do and why we need them  aNew DelhibIndiana publishing housec2009  axvi,253p.c24cm.bHB