@article{PORMA_1963__22_3_114901,
     author = {Morgado, Jos\'e},
     title = {Some remarks on the unitary analogue of the {Nagell} totient function},
     journal = {Portugaliae mathematica},
     pages = {127--135},
     publisher = {mathdoc},
     volume = {22},
     number = {3},
     year = {1963},
     zbl = {0122.05206},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PORMA_1963__22_3_114901/}
}