Strategy Design Pattern implementation - Payment types (Accounting and Transfer)

StrategyDesignPatternTransfer.cs

public interface ITransferOperation
    {
        bool DoAccounting();
        void Transfer();
    }

    public class ForeignPayment
        :ITransferOperation
    {
        public bool DoAccounting()
        {
            throw new NotImplementedException();
        }

        public void Transfer()
        {
            throw new NotImplementedException();
        }
    }

    public class DomesticPayment
        :ITransferOperation
    {
        public bool DoAccounting()
        {
            throw new NotImplementedException();
        }

        public void Transfer()
        {
            throw new NotImplementedException();
        }
    }

    public class SepaPayment
        : ITransferOperation
    {
        public bool DoAccounting()
        {
            throw new NotImplementedException();
        }

        public void Transfer()
        {
            throw new NotImplementedException();
        }
    }

    public class Payment
    {

        private readonly ITransferOperation _transfer;
        public Payment (ITransferOperation transfer)
	    {
            this._transfer = transfer;
	    }

        public bool DoAccounting()
        {
            this._transfer.DoAccounting();
            return default(bool);
        }

        public void Transfer()
        {
            this._transfer.Transfer();
        }
    }