WASET
	@article{(Open Science Index):https://publications.waset.org/pdf/13786,
	  title     = {Extending E-learning systems based on Clause-Rule model},
	  author    = {Keisuke Nakamura and  Kiyoshi Akama and  Hiroshi Mabuchi},
	  country	= {},
	  institution	= {},
	  abstract     = {E-Learning systems are used by many learners and
teachers. The developer is developing the e-Learning system. However,
the developer cannot do system construction to satisfy all of
users- demands. We discuss a method of constructing e-Learning
systems where learners and teachers can design, try to use, and share
extending system functions that they want to use; which may be nally
added to the system by system managers.},
	    journal   = {International Journal of Computer and Information Engineering},
	  volume    = {3},
	  number    = {4},
	  year      = {2009},
	  pages     = {1177 - 1183},
	  ee        = {https://publications.waset.org/pdf/13786},
	  url   	= {https://publications.waset.org/vol/28},
	  bibsource = {https://publications.waset.org/},
	  issn  	= {eISSN: 1307-6892},
	  publisher = {World Academy of Science, Engineering and Technology},
	  index 	= {Open Science Index 28, 2009},
	}