1. It is important to note that attention to the problem at hand is the crucial distinction in our definitions of conscious and unconscious thought. Thinking about buying a new car while attention is directed at possible new cars is conscious thought. Thinking about buying a new car while attention is temporarily directed elsewhere is unconscious thought. This distinction does not mean that conscious thought only comprises conscious processes. One can compare it to speech. Speech is a conscious process (i.e. attention is directed at it while one speaks) but it is in part dependent on accompanying unconscious processes (such as processes responsible for syntax or word choice).
2. The Philosophical Writings of Descartes 1984
3. An Essay Concerning Human Understanding 1689
4. Decision Making: A Psychological Analysis of Conflict Choice and Commitment 1977
5. A Behavioral Model of Rational Choice