00305nam a2200121 a 450000500170000002000150001708200160003210000220004824500480007025000120011826000310013030000220016120251203091329.0  a0876925069  a001.6,bcon  aCondon, Robert, J  aData processing systems analysis and design  a4th ed.  aDelhi: Prentice-Hallc1985  axiv,410p.c22 cm.