@article{01883721, title = {Complexity of terms, composition, and hypersubstitution.}, journal = {International Journal of Mathematics and Mathematical Sciences}, volume = {2003}, year = {2003}, pages = {959-969}, doi = {10.1155/S0161171203202118}, zbl = {1015.08005}, language = {en}, url = {http://dml.mathdoc.fr/item/01883721} }
Denecke, Klaus; Wismath, Shelly L. Complexity of terms, composition, and hypersubstitution.. International Journal of Mathematics and Mathematical Sciences, Tome 2003 (2003) pp. 959-969. doi : 10.1155/S0161171203202118. http://gdmltest.u-ga.fr/item/01883721/