K. Becker, G. Stumme, R. Wille, U. Wille, и M. Zickwolff. Knowledge Engineering and Knowledge Management. Methods, Models, and Tools., том 1937 из LNAI, стр. 352-365. Heidelberg, Springer, (2000)
G. Stumme. Conceptual Structures: Integration and Interfaces, том 2393 из LNAI, стр. 2-19. Heidelberg, Springer, (2002)Invited Talk, summary of stumme03offtonew.