Mona found a wallet on the floor of an elevator in the office building where she worked. She posted several notices in the building about finding the wallet, but no one appeared to claim it. She waited for six months and then spent the money in the wallet in the belief that she owned it. Jason, the person who lost the wallet, subsequently brought suit to recover the money. Mona's defense was that the money was hers because Jason did not claim it within a reasonable time after she posted the notices. Is she correct? (Assume the common law applies.)