000 00255nam a2200109Ia 4500
008 220201s9999 xx 000 0 eng d
100 _aHELD (GILBERT)
245 0 _aUNDER STANDING DATA CAMMUNCATIONS
250 _a4TH
260 _bTECHMEDIA
942 _2ddc
999 _c97521
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