00421nam a22001337a 4500008004100000020001500041040005500056080001800111245005900129260004900188300001400237650002200251653001400273230516b        |||||||| |||| 00| 0 eng d  a008034092X  aNational Science LibrarycNational Science Library  aD 681.3bM6.3  aCommunications standards c/ Pergamon Infotech Limited  aEngland: bPergamon Infotech Limited, c1986  ax, 486p.   aComputer science   aSoftware