00305nam a2200109 a 450000500170000002000150001708200150003210000160004724500750006326000390013830000180017720251203091754.0  a0824720571  a020.3bENC  aKent, Allen  aEncyclopedia of Library and Information science, Vol.57, Supplement-20  aNew YorkbMarcel Dekker,INC.c1996  a357p.c24 cm.