@article{02097213, title = {On the set of values of the Euler function.}, journal = {Vladikavkazski\u\i\ Matematicheski\u\i\ Zhurnal}, volume = {1}, year = {1999}, pages = {53-55}, zbl = {1052.11502}, language = {en}, url = {http://dml.mathdoc.fr/item/02097213} }
Tasoev, B.G. On the set of values of the Euler function.. Vladikavkazskiĭ Matematicheskiĭ Zhurnal, Tome 1 (1999) pp. 53-55. http://gdmltest.u-ga.fr/item/02097213/