[1] P. Erdös: On the multiplicative representation of integers. Israel J. Math. 2 (1964), 251 - 261. DOI 10.1007/BF02759742 | MR 0181619

[2] P. Erdös P. Turán: On a problem of Sidon in additive number theory, and on some related problems. J. London Math. Soc. 16 (1941), 212-215. MR 0006197

[3] M. B. Nathanson: Multiplicative representation of integers. Israel J. Math. 57 (1987), 129-136. DOI 10.1007/BF02772173 | MR 0890419

[4] J. Nešetřil V. Rödl: Two proofs in combinatorial number theory. Proc. Amer. Math. Soc. 93, (1985), 185-188. DOI 10.1090/S0002-9939-1985-0766553-0 | MR 0766553

[5] V. Puš: Combinatorial properties of products of graphs. Czech. Math. J. 41 (1991), 269-277. MR 1105442

[6] V. Puš: On multiplicative bases in commutative semigroups. (to appear to Europ. J. Combinatorics). MR 1164764