“…Assuming X is observed on a discrete grid {(t i , y k )} i=0,...,N,k=0,...,M ⊂ [0, T ] × [0, 1], approximate maximum likelihood estimators have been first investigated by Markussen [28] for T → ∞. For various linear SPDEs central limit theorems for method of moment type estimators based on realized quadratic variations have been studied by Torres et al [36], Cialenco and Huang [7], Cialenco and Kim [8], Bibinger and Trabs [2,3], Chong [4,5], Shevchenko et al [35], Liu and Tudor [25], as well as Kaino and Uchida [22]. However, all these works only give partial answers to the estimation problem.…”