Norman and Shallice’s Supervisory Attentional Control model (1980) was based on the Schneider and Schiffrin (1977) study that proposed automatic and controlled processing within routine and non-routine situations. SAS model distinguished between contention scheduling (lower-level mechanism activating or inhibiting schemata in routine circumstance for familiar and automatic response) and supervisory control (higher-level mechanism that controls contention scheduling to produce novel, flexible, planned response).
Schneider, W., & Shiffrin, R. M. (1977). Controlled and automatic human information processing: I. Detection, search, and attention. Psychological Review, 84(1), 1-66.
http://dx.doi.org/10.1037/0033-295X.84.1.1
Norman D.A., Shallice T. (1986) Attention to Action. In: Davidson R.J., Schwartz G.E., Shapiro D. (eds) Consciousness and Self-Regulation. Springer, Boston, MA