1. Operator effort and the measurement of heart-rate variability;Aasman;Hum. Factors,1987
2. Multimodal measures of mental workload during dual-task performance: Energetic demands of cognitive processes;Backs,1992
3. Psychophysiological measures of workload during continuous manual performance;Backs,1993
4. Working Memory;Baddeley,1986
5. Additional heart rate — An indicator of psychological activation;Blix;Aerosp. Med.,1974