@article{10_1017_S0017089519000041,
     author = {POLLACK, PAUL},
     title = {NONNEGATIVE {MULTIPLICATIVE} {FUNCTIONS} {ON} {SIFTED} {SETS,} {AND} {THE} {SQUARE} {ROOTS} {OF} \ensuremath{-}1 {MODULO} {SHIFTED} {PRIMES}},
     journal = {Glasgow mathematical journal},
     pages = {187--199},
     year = {2020},
     volume = {62},
     number = {1},
     doi = {10.1017/S0017089519000041},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S0017089519000041/}
}