[1]  Powell M J D. A direct search optimization method that models the objective and constrained functions by linear interpolation. Gomez S,  Hennart J P, eds. Advances in Optimization and Numerical Analysis. Dordrecht: Kluwer Academic, 1994:  51--67

[2]  Conn A R, Toint Ph L. An algorithm using quadratic interpolation for unconstrained optimization. Di Pillo G, Gianessi F, eds. Nonlinear Optimization and Applications. New York: Plenum Publishing, 1996: 27--47

[3]  Conn A R, Scheinberg  K, Toint Ph L. On the convergence of derivative free methods for unconstrained optimization. Iserles A, Buhmann M, eds. Approximation Theory and Optimization: Tributes to M J D Powell. Cambridge: Cambridge University Press, 1997: 83--108

[4]  Ni Q, Hu S H. A new derivative free optimization method based on conic interpolation model. ACTA Mathematica Scientia, Series B, 2004, 24(2): 281--290

[5]  Powell M J D. UOBYQA: unconstrained optimization by quadratic approximation. Math Program, 2002, 92: 555--582

[6]  Colson B, Toint Ph L. A derivative-free algorithm for sparse unconstrained optimization problems. Siddiqi A H, Kocvara M, eds. Trends in Industrial and Applied Mathematics, Vol 72 of Applied Optimization. The Netherlands Dordrecht:  Kluwer Academic Publishers, 2002: 131--147

[7]  Powell M J D. Direct search algorithms for optimization calculations. Acta Numerica, 1998, 7: 287--336

[8]  Conn A R, Scheinberg K, Toint Ph L. Recent progress in unconstrained nonlinear optimization without derivatives. Math  Program, 1997, 97: 397--414

[9]  Sauer T, Xu Y. On multivariate Lagrange interpolation. Mathematics of Computation, 1995, 64: 1147--1170

[10]  More J J. Recent development in algorithms and software for trust region methods. Bachem A, Grotschel M, Krote B, eds. Mathematical Programming: the State of the Art. Berlin: Springer Verlag, 1983: 258--287

[11]  More J J, Sorense D C. Computing a trust region step. SIAM J Sci Stat Comput, 1983, 4(3):553--572

[12]  Bongartz I, Conn A R, Gould I, Toint Ph L. CUTE: Constrained and unconstrained testing environment. ACM Transations on Mathematical
 Software, 1995, 21(1): 123--160