Walter Martin, The Kingdom of the Cults, (Grand Rapids: Zondervan, 1965; revised in several editions published by Bethany House in 1967, 1977, 1985, 1997 and 2003).
J. Gordon Melton, "The counter-cult monitoring movement in historical perspective," in Challenging Religion: Essays in Honour of Eileen Barker, edited by James A. Beckford & James T. Richardson, (Routledge, London, 2003), pp. 102-113.
Larry Nichols and George Mather, Discovering the Plain Truth: How the Worldwide Church of God Encountered the Gospel of Grace (Downers Grove: Intervarsity Press, 1998).
Joseph Tkach, Transformed By Truth (Sisters, Oregon: Multnomah, 1997).