protected virtual ProductInfo SelectProducto()
        {
            ProductList lista = ProductList.GetList(_acreedor, _serie, false, true);

            ProductSelectForm form = new ProductSelectForm(this, lista);

            form.ShowCodigoProveedor(true);

            if (form.ShowDialog(this) == DialogResult.OK)
            {
                ProductInfo producto = (form.Selected as ProductInfo);
                return(producto);
            }

            return(null);
        }