“Boredom and the Yawn,” Linda A. Bell, Review of Existential Psychology and Psychiatry, vol. 17, no. 1, 1980-1981, pp. 91-100. In it, Bell:
Discusses Sartre’s views in Nausea on boredom and the yawn, asserting that boredom is connected with facticity — the aspect of self most closely connected with the being of things–and not with freedom and transcendence. This state is contrasted with an authentic embrace of freedom and transcendence. It is concluded that individuals can become bored with their own freedom and that boredom, or its possibility, plays a role in an ethics of authenticity developing out of Sartre’s thought.
(That’s an excerpt from the article “A Smattering of Yawns (Some research highlights,) published in AIR 11:1.)