Size of Quantum Versus Deterministic Finite Automata. - Andris Ambainis; Uldis Barbans; Agnese Belousova; Aleksandrs Belovs; Ilze Dzelme; Girts Folkmanis; Rusins Freivalds; Peteris Ledins; Rihards Opmanis; Agnis Skuskovniks (VLSI, 2003)

Combinatorial Block Designs for Quantum Computing Problems. - Rusins Freivalds; Elina Kalnina; Rihards Opmanis; Agnese Zalcmane (FCS, 2005)

Integer Complexity: Experimental and Analytical Results II. - Juris Cernenoks; Janis Iraids; Martins Opmanis; Rihards Opmanis; Karlis Podnieks (DCFS, 2015)