00326nam a2200121 a 450000500170000002000150001708200170003210000060004911000200005524500770007526000330015230000190018520251203092230.0  a083890405X  a300.16,bsou  d_  aWebb, William,H  aSources of information in the social sciences: a guide to the literature  aDelhi:Arnold Heinemannc1987  ax, 777p.c22cm