id author title date pages extension mime words sentence flesch summary cache txt crl-11731 Leffler, William L. A Statistical Method for Circulation Analysis 1964-11-01 3 .pdf application/pdf 1571 97 77 If we have less copies, the acquisition of additional copies is ration- ally justified, since we expect that we will have occasions when we will not be able to provide a customer with his requested text. Would it not be conveni- ent to look at a chart like this and judge visually the maximum number of copies that were in use? cache/crl-11731.pdf txt/crl-11731.txt