V. Batyrev and Y. Tschinkel, Tamagawa numbers of polarized algebraic varieties, Astérisque, vol.251, pp.299-340, 1998.

R. De-la-bretèche, Sur le nombre de points de hauteur bornée d'une certaine surface cubique singulì ere, Astérisque, vol.251, pp.51-77, 1998.

R. De-la-bretèchebretèche, T. Browning, and P. Salberger, Counting rational points on the Cayley ruled cubic, European Journal of Mathematics, vol.251, issue.1, pp.55-72, 2016.
DOI : 10.1007/978-3-663-10632-6

R. De-la-bretèche, J. Liu, J. Wu, and Y. Zhao, On a certain non-split cubic surface

E. Grosswald, Representations of integers as sums of squares, pp.0-387, 1985.
DOI : 10.1007/978-1-4613-8566-0

H. Iwaniec, Topics in classical automorphic forms, Graduate Studies in Mathematics, vol.17, 1997.
DOI : 10.1090/gsm/017

J. Liu, J. Wu, and Y. Zhao, Manin???s Conjecture for a Class of Singular Cubic Hypersurfaces, International Mathematics Research Notices, vol.448, issue.3, pp.1-36
DOI : 10.1090/conm/448/08668

URL : http://arxiv.org/pdf/1703.06148

G. Tenenbaum, Introduction to analytic and probabilistic number theory, Translated from the second French edition, Cambridge Studies in Advanced Mathematics, vol.46, 1995.
DOI : 10.1090/gsm/163

J. Wu and C. Umr, Laboratoire d'analyse et de mathématiques appliquées 94010 Créteil cedex, France E-mail address: jie.wu@math.cnrs.fr Yongqiang Zhao