1. Daley, M., Kari, L., Gloor, G., Siromoney, R.: Circular contextual insertions/deletions with applications to biomolecular computation. In: Proc. of 6th Int. Symp. on String Processing and Information Retrieval, SPIRE1999, Cancun, Mexico, pp. 47–54 (1999)
2. Galiukschov, B.S.: Semicontextual grammars. In: Matematika Logica i Matematika Linguistika, Tallin University, pp. 38–50 (1981) (in Russian)
3. Kari, L.: On insertion and deletion in formal languages, PhD Thesis, University of Turku (1991)
4. Kari, L., Păun, G., Thierrin, G., Yu, S.: At the crossroads of DNA computing and formal languages: characterizing RE using insertion-deletion systems. In: Proc. of 3rd DIMACS Workshop on DNA Based Computing, Philadelphia, pp. 318–333 (1997)
5. Kari, L., Thierrin, G.: Contextual insertion/deletion and computability. Information and Computation 131(1), 47–61 (1996)