1. Theory of Fractional Dynamic Systems;Lakshmikantham,2009
2. V. Lakshmikantham, S. Leela, Nagumo-type uniqueness result for fractional differential equations, J. Nonlinear Anal., in press (doi:10.1016/j.na.2009.01.169)
3. Uniqueness and Non-uniqueness Criteria for Ordinary Differential Equations;Agarwal,1993