Scott Contini, Ernie Croot, Igor Shparlinski. Complexity of inverting the Euler function. Math. Comput., 75(254):983-996, 2006. [doi]
@article{ContiniCS06,
title = {Complexity of inverting the Euler function},
author = {Scott Contini and Ernie Croot and Igor Shparlinski},
year = {2006},
doi = {10.1090/S0025-5718-06-01826-6},
url = {http://dx.doi.org/10.1090/S0025-5718-06-01826-6},
researchr = {https://researchr.org/publication/ContiniCS06},
cites = {0},
citedby = {0},
journal = {Math. Comput.},
volume = {75},
number = {254},
pages = {983-996},
}