00313nam a2200133Ia 4500008004100000041001200041082002100053100002400074245002100098250001200119260002500131300001100156650001200167231217s9999    xx            000 0 und d  aEnglish  a621.3192  VAL;17  aValkenburg, Van M E 0aNetwork analysis  a3rd ed.  c1974bPHIaNew Delhi  axv+571  aNetwork