OutkaG (1977) Agape: An ethical analysis. New Haven, CT: Yale University Press.
2.
PetersonCSeligmanMEP (2004) Character strengths and virtues: A handbook and classification. Oxford: Oxford University Press.
3.
VerkuylJ (1988) Contemporary Missiology: An introduction. Grand Rapids, MI: William. B. Eerdmans Publishing Company.
4.
WrightNT (1997) What Saint Paul really said: Was Paul of Tarsus the Real Founder of Christianity?Grand Rapids, MI: William B. Eerdmans Publishing Company.