@article{JIS_2008__11_1_a1,
     author = {Noe, Tony D.},
     title = {Primes in classes of the iterated totient function},
     journal = {Journal of integer sequences},
     publisher = {mathdoc},
     volume = {11},
     number = {1},
     year = {2008},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/JIS_2008__11_1_a1/}
}