1. On the representation of continuous functions of several variables by superposition of continuous functions of one variable and addition;Kolmogorov;Dokl. Akad. Nauk SSSR,1957
2. On the representation of continuous functions of several variables by superposition of continuous functions of one variable and addition;Kolmogorov;Dokl. Akad. Nauk MR 22,1957
3. On the representation of continuous functions of many variables by superposition of continuous functions of one variable and addition
4. Improvement in the smoothness of functions in the Kolmogorov superposition theorem;Fridman;Dokl. Akad. Nauk SSSR,1967
5. Improvement in the smoothness of functions in the Kolmogorov superposition theorem;Fridman;Dokl. Akad. Nauk MR 38,1967