@article{00179256, title = {An identity for a class of arithmetical functions of several variables.}, journal = {International Journal of Mathematics and Mathematical Sciences}, volume = {16}, year = {1993}, pages = {355-358}, doi = {10.1155/S0161171293000432}, zbl = {0774.11007}, language = {en}, url = {http://dml.mathdoc.fr/item/00179256} }
Haukkanen, Pentti. An identity for a class of arithmetical functions of several variables.. International Journal of Mathematics and Mathematical Sciences, Tome 16 (1993) pp. 355-358. doi : 10.1155/S0161171293000432. http://gdmltest.u-ga.fr/item/00179256/