Free Retrivel U.S Patent Database on Internet
Yang Zhiping
New Technology of Library and Information Service . 1998, (2): 34 -36 .  DOI: 10.11925/infotech.1003-3513.1998.02.11

Copyright © Data Analysis and Knowledge Discovery, All Rights Reserved.
Tel: (010)82626611-6626，82624938　
E-mail：jishu@mail.las.ac.cn
Total visitors:   Visitors of today:   Now online:
Powered by Beijing Magtech Co. Ltd.