Konyagin, S. V., and I. D. Shkredov. “On One Result of J. Bourgain”.
Ukrains’kyi Matematychnyi Zhurnal
, vol. 62, no. 3, Mar. 2010, pp. 332–368,
https://umj.imath.kiev.ua/index.php/umj/article/view/2872
.