@article{1255629815, author = {Tull, J. P.}, title = {Average order of arithmetic functions}, journal = {Illinois J. Math.}, volume = {5}, number = {1}, year = {1961}, pages = { 175-181}, language = {en}, url = {http://dml.mathdoc.fr/item/1255629815} }
Tull, J. P. Average order of arithmetic functions. Illinois J. Math., Tome 5 (1961) no. 1, pp. 175-181. http://gdmltest.u-ga.fr/item/1255629815/