篇号：1
题名：On the estimation of returns to scale using variable cost functions
作者：Ronald R. Braeutigam，Andrew F. Daughety
期刊全称或缩写：Economics Letters
年份，卷（期），起止页码：Volume 11, Issues 1-2, 1983, Pages 25-31
电子链接：http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V84-45BC710-6&_user=2321961&_coverDate=12%2F31%2F1983&_alid=983046334&_rdoc=3&_fmt=high&_orig=search&_cdi=5860&_sort=r&_docanchor=&view=c&_ct=17&_acct=C000056894&_version=1&_urlVersion=0&_userid=2321961&md5=dba71f7b63e28a2fabdeac1f53db2887

篇号：2
题名：Economies of scale and density in local telephone networks
作者：Jean-Michel Guldmann
期刊全称或缩写：Regional Science and Urban Economics
年份，卷（期），起止页码：Volume 20, Issue 4, February 1991, Pages 521-535
电子链接：http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V89-45DMR4F-2M&_user=2321961&_coverDate=02%2F28%2F1991&_alid=983046334&_rdoc=5&_fmt=high&_orig=search&_cdi=5865&_sort=r&_docanchor=&view=c&_ct=17&_acct=C000056894&_version=1&_urlVersion=0&_userid=2321961&md5=1b52cce762c62307ba588b57136ff4d2