private void btnAtras_Click(object sender, EventArgs e)
{
this.Visible = false;
Citas citas = new Citas(this.conexion);
citas.ShowDialog();
}
private void citasToolStripMenuItem_Click(object sender, EventArgs e)
{
this.Visible = false;
Citas citas = new Citas(this.conexion);
citas.ShowDialog();
}