Your search returned the following 2 documents:

2. System Description: SPASS Version 1.0.0
   Christoph Weidenbach, Bijan Afshordel, Uwe Brahm, Christian Cohrs, Thorsten Engel, Enno Keen, Christian Theobalt, and Dalibor Topić
   In: Proceedings of the 16th International Conference on Automated Deduction (CADE-16), Trento, Italy, 1999, 314-318
   
1. First-Order Atom Definitions Extended
   Bijan Afshordel, Thomas Hillenbrand, and Christoph Weidenbach
   In: Proceedings of the 8th International Conference on Logic for Programming, Artificial Intelligence, and Reasoning (LPAR-2001), Havanna, Cuba, December, 3 - December, 7, 2001, 309-319
   [PS: Download: AtomFinal.ps]