10027/12729 Zhilong. Zhang Zhilong. Zhang Enumeration of general t-ary trees and universal types. University of Illinois at Chicago 2014 Mathematics. 2014-03-17 00:00:00 Thesis https://indigo.uic.edu/articles/thesis/Enumeration_of_general_t-ary_trees_and_universal_types_/10795982 Enumeration of general t-ary trees and universal types.