Régis de la Bretèche, Andrew Granville, “Exponential sums with multiplicative coefficients and applications”, Trans. Amer. Math. Soc., 375:10 (2022), 6875
Maxim Korolev, Igor Shparlinski, “Sums of algebraic trace functions twisted by arithmetic functions”, Pacific J. Math., 304:2 (2020), 505–522