A coalgebraic view of in trees and iteration (2001)

by P Aczel, J Adamek, J Velebil
Venue:Proc. of 4th Wksh. on Coalgebraic Methods in Computer Science, CMCS'01 (Genova, Apr. 2001), Electr. Notes in Theoret. Comput. Sci. 44(1), Elsevier