private void AddSourceButton_Click(object sender, RoutedEventArgs e)
        {
            try
            {
                _SQLClient.InsertSource(
                    SourceNameTextBox.Text,
                    SourceAuthorTextBox.Text,
                    int.Parse(SourceYearTextBox.Text)
                    );

                Frames.Sources.Instance.SelectSources();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, "Ошибка");
            }

            Frames.Properties.Instance.RefreshDataGrid();
        }