1. Baron, K. andJarczyk, W.,On a way of division of segments. Aequationes Math.34 (1987), 195–205.
2. Dhombres, J. G.,Itération linéaire d'ordre deux. Publ. Math. Debrecen24 (1977), 277–287.
3. Dhombres, J.,Some aspects of functional equations. Chulalongkorn University Press, Bangkok, 1979.
4. Jarczyk, W.,A recurrent method of solving iterative functional equations. Prace Nauk. Uniw. Ślask. Nr 1206, Katowice, 1991.
5. Monografie Mat.;M. Kuczma,1968