The Virtue of Selfishness by Ayn Rand
Ayn Rand explains her revolutionary concept of rational self-interest.

In Defense of Selfishness: Why the Code of Self-Sacrifice is Unjust and Destructive by Peter Schwartz 
Basing his arguments on Ayn Rand’s ethics of rational self-interest, Schwartz demonstrates that genuine selfishness is not exemplified by the brutal plundering of an Attila the Hun or the conniving duplicity of a Bernard Madoff. To the contrary, such people are acting against their actual, long-range interests. The truly selfish individual is committed to moral principles and lives an honest, productive, self-respecting life. He does not feed parasitically off other people. Instead, he renounces the unearned and deals with others—in both the material and spiritual realms—by offering value for value, to mutual benefit.

Viable Values: A Study of Life as the Root and Reward of Morality by Tara Smith
Dr. Smith provides an academic presentation of An Rand’s Objectivist ethics.

Ayn Rand’s Normative Ethics: The Virtuous Egoist by Tara Smith
The Virtuous Egoist examines the nature of the essential virtues — rationality, honesty, independence, justice, integrity, productiveness, and pride — and what they demand in practice while addressing the status of conventional traits such as kindness, charity, generosity, temperance, courage, forgiveness, and humility.