In this paper, we elucidate the well-known Wilton’s formula for the product of two Riemann zeta functions. A proof of Wilton’s expression for product of two zeta functions was given by M. Nakajima in~ using the Atkinson dissection. On the similar line we derive Wilton’s formula using the Riesz sum of the order $\kappa=1$.
Debika Banerjee. Jay Mehta. "Linearized product of two Riemann zeta functions." Proc. Japan Acad. Ser. A Math. Sci. 90 (8) 123 - 126, October 2014. https://doi.org/10.3792/pjaa.90.123