On Language Equations XXK = XXL and XM = N over a Unary Alphabet. - Tommi Lehtinen 001; Alexander Okhotin (Developments in Language Theory, 2010)

Boolean Grammars and GSM Mappings. - Tommi Lehtinen 001; Alexander Okhotin (Int. J. Found. Comput. Sci., 2010)

On Equations over Sets of Numbers and their Limitations. - Tommi Lehtinen 001; Alexander Okhotin (Int. J. Found. Comput. Sci., 2011)

Equations X + A = B and (X + X) + C = (X - X) + D over Sets of Natural Numbers. - Tommi Lehtinen 001 (MFCS, 2012)

Homomorphisms Preserving Deterministic Context-Free Languages. - Tommi Lehtinen 001; Alexander Okhotin (Int. J. Found. Comput. Sci., 2013)