1. Arithmetical functions in several variables;Alkan, Emre;Int. J. Number Theory,2005
2. Multidimensional averages and Dirichlet convolution;Alkan, Emre;Manuscripta Math.,2007
3. Ramanujan’s unpublished manuscript on the partition and tau functions with proofs and commentary;Berndt, Bruce C.;S\'{e}m. Lothar. Combin.,1999
4. The ring of number-theoretic functions;Cashwell, E. D.;Pacific J. Math.,1959
5. On a class of arithmetical convolutions;Narkiewicz, W.;Colloq. Math.,1963