1. Besicovitch A.S., On the linear independence of fractional powers of integers, J. London Math. Soc., 1940, 15, 3–6
2. Chung D., Petridis Y.N., Toth J.A., The remainder in Weyl’s law for Heisenberg manifolds II, In: Heath-Brown D.R. et al (Eds.), Proceedings of the session in analytic number theory and Diophantine equations ( January–June 2002, Bonn, Germany) Bonner Mathematische Schriften, 2003, 360
3. Corrádi K., Kátai I., A comment on K.S. Gangadharan’s paper “Two classical lattice point problems”, Magyar Tud. Akad. Mat. Fiz. Tud. Oszt. Kozl., 1967, 17, 89–97 (in Hungarian)
4. Cramér H., Über zwei Sätze von Herrn G.H. Hardy, Math. Z., 1922, 15, 201–210
5. Drmota M., Tichy R.F., Sequences, discrepancies, and applications, Lecture Notes in Math. 1651, Springer, Berlin, 1997