Further discussions:
Ayn Rand, "The Objectivist Ethics," in The Virtue of Selfishness: A New Concept of Egoism (New York: The New American Library, 1964), pp. 19-20, 22.

Nathaniel Branden, "Mental Health Versus Mysticism and Self-Sacrifice," in The Virtue of Selfishness: A New Concept of Egoism (New York: The New American Library, 1964), pp. 40-41.

Nathaniel Branden, "The Psychology of Pleasure," in The Virtue of Selfishness: A New Concept of Egoism (New York: The New American Library, 1964), pp. 81-83.

Nathaniel Branden, The Psychology of Self-Esteem: A New Concept of Man's Psychological Nature (New York: Bantam Books, 1969), pp. 124-127, 241-242.

Leonard Peikoff, Objectivism: The Philosophy of Ayn Rand (New York: Dutton, 1991), pp. 303-310.

Tara Smith, "The Practice of Pride," Social Philosophy & Policy v. 15, no. 1 (Winter 1998), pp. 71-90. [Available on the 5th floor of the Main Library (UGA) at H61.S6.]

Tara Smith, Ayn Rand's Normative Ethics: The Virtuous Egoist (Cambridge: Cambridge University Press, 2006), pp. 221-246.