E. Beck, и V. Bellotti. Proceedings of the third conference on Computer Cooperative Work, стр. 233-248. Milan, Italy, Kluwer Academic Publishers, Dordrecht, (1993)
K. Beck, и R. Johnson. Proceedings of European Conference on Object-Oriented Programming ECOOP'94, том 821 из LNCS, стр. 139--149. Springer-Verlag, (июля 1994)