Before revision:  In this article we consider an approach to gas storage valuation in which the information about the time at which the holder of a gas storage contract should choose to inject or withdraw gas is modelled using a Brownian bridge that starts at zero and is conditioned to equal a constant x in the time of injection and a constant y in the time of withdrawal.
After revision:  In this article we consider an approach to gas storage valuation in which the information about the time at which the holder of a gas storage contract should choose to inject or withdraw gas is modelled using a Brownian bridge that starts at zero and is conditioned to equal a constant x in the time of injection , and to a constant y in the time of withdrawal.