1. Buswell, S., Caprotti, O., Carlisle, D., Dewar, M., Gaetano, M., Kohlhase, M.: The Open Math Standard, Version 2.0. Technical report, The Open Math Society (2004),
http://www.openmath.org/standard/om20
2. Lecture Notes in Computer Science;M. Codescu,2011
3. Lecture Notes in Computer Science;J. Giceva,2009
4. Harper, R., Honsell, F., Plotkin, G.: A framework for defining logics. Journal of the Association for Computing Machinery 40(1), 143–184 (1993)
5. Lecture Notes in Computer Science;F. Horozal,2011