An Isometric Approach to Generalized Stochastic Integrals

The possibility to extend the classical Itoʹʹs construction of stochastic integrals is studied. This construction can be applied to fractional Brownian motions with Hurst index H (element of) (0, 1/2). A change of variables formula for fractional Brownian motions in terms of the stochastic integrals is given.