This author has not been identified. Look up 'Martin Balko' in GoogleThis author has not been identified. Look up 'Attila Pór' in GoogleThis author has not been identified. Look up 'Manfred Scheucher' in GoogleThis author has not been identified. Look up 'Konrad J. Swanepoel' in GoogleThis author has not been identified. Look up 'Pavel Valtr' in Google