求文献三篇，非常感谢！！

篇号：1
题名：Econometric Cost Structure Estimates for Cellular Telephony in the United States
作者：David J. McKenzie1 and John P. Small
期刊全称或缩写：Journal of Regulatory Economics
年份，卷（期），起止页码：Volume 12, Number 2 / 1997年9月，147-157
电子链接：http://www.springerlink.com/content/w0527126h6114727/
篇号：2
题名：Estimating scale economies of the wireless telecommunications industry using EVA data
作者：Changi Nama, Youngsun Kwona, Seongcheol Kimb, Hyeongjik Leec
期刊全称或缩写：Telecommunications Policy,
年份，卷（期），起止页码：Volume 33, Issues 1-2, February-March 2009, Pages 29-40
电子链接：http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VCC-4V4KCF2-1&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=981412429&_rerunOrigin=scholar.google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=a347a64a0a45191bae708f39297a3011
篇号：3
题名：A Composite Cost Function for Multiproduct Firms With An Application to Economies of Scope in Banking
作者：Lawrence B. Pulley and Yale M. Braunstein
期刊全称或缩写：The Review of Economics and Statistics
年份，卷（期），起止页码：Vol. 74, No. 2 (May, 1992), pp. 221-230
电子链接：http://www.jstor.org/pss/2109653