Correction of psycho-emotional stress among primary schoolchildren with special educational needs with the use of biofeedback - R. A. Kistenyova; Yu. V. Kistenyov; Ya. S. Pekker; K. S. Brazovskiy; N. G. Brazovskaya; V. A. Fokin (Бюллетень сибирской медицины, 2010)