S matrix representation in terms of functional integration

On the basis of functional integral in configurational space S-matrix expression in holomorphic representation is derived. The obtained expression permits to calculate S matrix if behaviour of two-time Green functions on time infinities is known. To simplify the presentation authors consider only one-dimensional quantum-mechanical anharmonic oscillator. All formulas derived in this model are simply extended to the field theory, though, for existence of S matrix the introduction of interaction factor is necessary