Cycle Height of Finite Automata. - Chris Keeler; Kai Salomaa (DCFS, 2018)

Nondeterminism Growth and State Complexity. - Chris Keeler; Kai Salomaa (DCFS, 2019)

Branching Measures and Nearly Acyclic NFAs. - Chris Keeler; Kai Salomaa (Int. J. Found. Comput. Sci., 2019)

Combining Limited Parallelism and Nondeterminism in Alternating Finite Automata. - Chris Keeler; Kai Salomaa (DCFS, 2020)

Alternating Finite Automata with Limited Universal Branching. - Chris Keeler; Kai Salomaa (LATA, 2020)

Width Measures of Alternating Finite Automata. - Chris Keeler; Kai Salomaa (DCFS, 2021)

Finite Automata with Restricted Nondeterminism and Universality - Chris Keeler (2021)

Structural properties of NFAs and growth rates of nondeterminism measures. - Chris Keeler; Kai Salomaa (Inf. Comput., 2022)