“…Because Λ (that can be formally written as Λ(x − y) = H(2H − 1)|x − y| 2H−2 ) is not a locally integrable function, the classical approach developed, among others, by Da Prato and Zabczyk [6], Peszat and Zabczyk [14], Dalang in [7,8] and Dalang and Quer-Sardanyons [9], cannot be applied to such rough covariance. In [1], Balan, Jolis and Quer-Sardanyons proved the existence and uniqueness of a mild solution to equation (1.1) in the particular case σ(u) = au + b, and assuming that the initial condition u 0 is bounded and Hölder continuous of order H. The stochastic integral is understood in the Itô sense.…”