Degrees of Ambiguity of Büchi Tree Automata. - Alexander Rabinovich; Doron Tiferet (FSTTCS, 2019)

Ambiguity Hierarchy of Regular Infinite Tree Languages. - Alexander Rabinovich; Doron Tiferet (MFCS, 2020)

Degrees of Ambiguity for Parity Tree Automata. - Alexander Rabinovich; Doron Tiferet (CSL, 2021)