Probabilities to Accept Languages by Quantum Finite Automata. - Andris Ambainis; Richard F. Bonner; Rusins Freivalds; Arnolds Kikusts (COCOON, 1999)

On the Class of Languages Recognizable by 1-Way Quantum Finite Automata. - Andris Ambainis; Arnolds Kikusts; Maris Valdats (STACS, 2001)

Exact results for accepting probabilities of quantum automata. - Andris Ambainis; Arnolds Kikusts (Theor. Comput. Sci., 2003)

Algebraic Results on Quantum Automata. - Andris Ambainis; Martin Beaudry; Marats Golovkins; Arnolds Kikusts; Mark Mercer; Denis Thérien (Theory Comput. Syst., 2006)