[1] E. Asplund, R. T. Rockafellar: Gradients of convex functions. Trans. Amer. Math. Society 189 (1969), 443-467. MR 0240621 | Zbl 0181.41901

[2] A. Auslender: Optimization, Methodes Numeriques. Masson, Paris 1976. MR 0441204

[3] V. I. Blagodatskich: On the convexity of reachable sets. (in Russian). Differenciaľnye Uravnenija VIII (1972), 2149-2155.

[4] F. L. Chernousko, N. V. Banichuk: Variational Problems of Mechanics and Control. (in Russian). Nauka, Moskva 1973.

[5] A. Charnes, W. W. Cooper: Programming with linear fractional functional. Naval Res. Logist. Quart. 9 (1962), 181-196. MR 0152370

[6] R. J. Duffin E. L. Peterson, C. Zener: Geometric Programming - Theory and Application. J. Wiley and Sons, New York 1967. MR 0214374

[7] R. E. Edwards: Functional Analysis - Theory and Applications. Holt, Rinehart ard Winston, New York 1965. MR 0221256 | Zbl 0182.16101

[8] I. Ekeland, R. Temam: Analyse Convexe et Problèmes Variationnels. Dunod, Paris 1974. MR 0463993 | Zbl 0281.49001

[9] E. G. Golshtein: Gradient methods for determination of saddle points and modified Lagrangians. In: Proc. of the Workshop "Matem. Optimierung - Theorie und Anwendungen", Wartburg/Eisenach 1983.

[10] M. R. Hestenes: Multiplier and gradient methods. J. Optimiz. Theory Appl. 4 (1969), 303-320. MR 0271809 | Zbl 0208.18402

[11] O. A. Ladyzhenskaya: Boundary Value Problems of Mathematical Physics. (in Russian). Nauka, Moskva 1973. MR 0599579

[12] C. Lemaréchal: Nondifferentiable optimization, subgradient and $\epsilon$-subgradient methods. In: Numerical Methods in Optimization and Operations Research (Proc. of a Conference held at Oberwolfach, 1975), Springer Verlag, Berlin 1976. MR 0496691

[13] C. Lemaréchal: A view of line-searches. In: Optimization and Optimal Control (Proc. of a Conference held at Oberwolfach, 1980, A. Auslender, W. Oettli, J. Stoer, eds.), Springer Verlag, Berlin 1981. MR 0618474

[14] P. O. Lindberg: A generalization of Fenchel conjugation giving generalized Lagrangians and symmetric nonconvex duality. In: Survey of Mathematical Programming (Proc. of the 9th Internat. Mathematical Programming Symp., A Prekopa, ed.), Budapest 1976.

[15] P. O. Lindberg: Report TRITA-MAT-1976-12. Dept. of Math., Royal Inst, of Technology, Stockholm.

[16] D. E. Luenberger: Optimization by Vector Space Methods. J. Wiley and Sons, New York 1968.

[17] G. P. McCormick: Nonlinear Programming. J. Wiley and Sons, New York 1983. MR 0693095 | Zbl 0563.90068

[18] G. D. Maistrovskii: Gradient methods for finding saddle points. (in Russian). Ekonom. i Mat. Metody 12 (1976), 917-929. MR 0451122

[19] J. J. Moreau: Proximité et dualité dans un espace Hilbertian. Bull. Soc. Math. France 93 (1965),273-299. MR 0201952

[20] J. V. Outrata: Duality theory for a class of discrete optimal control problems. In: Proc. 1978 IFAC Congress, 2, 1085-1092, Pergamon Press, London 1978.

[21] J. V. Outrata, Z. Schindler: Augmented Lagrangians for a class of convex continuous optimal control problems. Problems Control Inform. Theory 10 (1981), 67-81. MR 0618443

[22] J. V. Outrata, J. Jarušek: On Fenchel dual schemes in convex optimal control problems. Kybernetika 18 (1982), 1-21. MR 0679777

[23] B. T. Polyak: A general method for solution of extremal problems. Doklady AN SSSR 174 (1967), 33-36. In Russian. MR 0217997

[24] B. T. Polyak: Minimization of nonsmooth functionals. Zh. vych. mat. i mat. fiz. 9 (1969) 504-521. In Russian. MR 0250452

[25] J. Ch. Pomerol, P. Levine: Sufficient conditions for Kuhn-Tucker vectors in convex programming. SIAM J. Control Optimiz. 17 (1976), 689-699. MR 0548698

[26] M. J. D. Powell: A method for nonlinear constraints in minimization problems. In: Optimization (R. Fletcher, ed.), Academic Press, New York 1969, 283 - 298. MR 0272403 | Zbl 0194.47701

[27] R. T. Rockafellar: Extension of Fenchel's duality theorem for convex functions. Duke Math. J. ii(1966), 81-89. MR 0187062 | Zbl 0138.09301

[28] R. T. Rockafellar: Integrals which are convex functionals. Pacific J. Math. 24 (1968), 525-539. MR 0236689 | Zbl 0159.43804

[29] R. T. Rockafellar: Some convex programs whose duals are linearly constrained. In: Non-linear Programming (J. B. Rosen, O. L. Mangasarian, K. Ritter, eds.), Academic Press, New York 1970, 293-322. MR 0281500 | Zbl 0252.90046

[30] R. T. Rockafellar: A dual approach to solving nonlinear programming problems by unconstrained optimization. Math. Programming 5 (1973), 354-373. MR 0371416 | Zbl 0279.90035

[31] R. T. Rockafellar: The multiplier method of Hestenes and Powell applied to convex programming. J. Optimiz. Theory Appl. 12 (1973), 555 - 562. MR 0334953 | Zbl 0254.90045

[32] R. T. Rockafellar: Conjugate Duality and Optimization. SIAM/CBMS monograph series No. 16, SIAM Publications, 1974. MR 0373611 | Zbl 0296.90036

[33] S. Schaible: Parameter-free convex equivalent and dual programs of fractional programming problems. Z. Oper. Res. 18 (1974), 187-196. MR 0351464 | Zbl 0291.90067

[34] S. Schaible: Duality in fractional programming: A unified approach. Oper. Res. 24 (1976), 452-461. MR 0411644 | Zbl 0348.90120

[35] S. Schaible: Fractional programming. I. Duality. Management Sci. 22 (1976), 858-867. MR 0421679 | Zbl 0338.90050

[36] J. F. Toland: Duality in nonconvex optimization. J. Math. Anal. Appl. 66 (1978), 399-415. MR 0515903 | Zbl 0403.90066

[37] J. F. Toland: A duality principle for non-convex optimisation and the calculus of variations. Arch. Rat. Mech. Anal. 71 (1979), 41-61. MR 0522706 | Zbl 0411.49012

[38] A. P. Wierzbicki, S. Kurcyusz: Projection on a cone, penalty functionals and duality theory for problems with inequality constraints in Hilbert space. SIAM J. Control Optimiz. 75 (1977), 25-56. MR 0438720 | Zbl 0355.90045

[39] J. Nedoma: Contribution to the Arrow-Hurwicz concave programming method. Ekonomicko-matematický obzor 2 (1966), 247-260. MR 0204160

[40] K. J. Arrow, L. Hurwicz: Reduction of constrained maxima to saddlepoint problems. In: Proc. of 3-rd Berkeley Symposium on Mathematical Statistical and Probability. Univ. of California Press, Berkeley 1956. MR 0084938

[41] K. J. Arrow F. J. Gould, S. M. Howe: A generalized saddle-point result for constrained optimization. Math. Programming 5 (1973), 225-234. MR 0329641

[42] M. Atteia, A. El Quortobi: Quasi-convex duality. In: Optimization and Optimal Control (Proc. of a Conf. Held at Oberwolfach March 1980; A. Auslender, W. Oettli, J. Stoer, eds.). L. N. in Control Inform. Sci., Vol. 30, Springer-Verlag, Berlin 1981.

[43] E. J. Balder: An extension of duality-stability relations to nonconvex optimization problems. SIAM J. Control Optim. 75 (1977), 329-343. MR 0452694 | Zbl 0366.90103

[44] A. Ben-Tal, A. Ben-Israel: F-convex functions: properties and applications. In: Generalized Concavity in Optimization and Economics. Academic Press, New York 1981. Zbl 0535.90074

[45] D. P. Bertsekas: Combined primal-dual and penalty methods for constrained minimization. SIAM J. Control 13 (1975), 521-544. MR 0372719 | Zbl 0269.90044

[46] D. P. Bertsekas: Constrained-Optimization and Lagrange Multiplier Methods. Academic Press, New York 1982. MR 0690767 | Zbl 0572.90067

[47] J. D. Buys: Dual Algorithms for Constrained Optimization. Thesis, Leiden 1972. MR 0334506

[48] B. D. Craven: Invex functions and constrained local minima. Bull. Austral. Math. Soc. 24 (1981), 357-366. MR 0647362 | Zbl 0452.90066

[49] J. P. Crouzeix: Conjugacy in quasiconvex analysis. In: Convex Analysis and Its Applications. (Proc. of a Conference Held at Murat-le-Quaire, March 1976, A. Auslender, ed.). L. N. in Econom. and Math. Systems, Vol. 144. Springer-Verlag, Berlin 1977. MR 0482465

[50] J. P. Crouzeix: Conditions for convexity of quasiconvex functions. Math. Oper. Res. 5 (1980), 120-125. MR 0561160 | Zbl 0428.26007

[51] J. P. Crouzeix, J. A. Ferland: Criteria for quasiconvexity and pseudoconvexity and their relationships. In: Generalized Concavity in Optimization and Economics. Academic Press, New York 1981. Zbl 0538.90079

[52] V. F. Demyanov, V. N. Malozemov: An Introduction to Minimax. (in Russian). Nauka, Moscow 1972. MR 0475822

[53] R. Deumlich, K.-H. Elster: $\phi$-conjugation and nonconvex optimization. Math. Operationsforsch. Statist. Ser. Optim. 14 (1983), 125-149. MR 0694807 | Zbl 0524.90081

[54] S. Dolecki, S. Kurcyusz: On $\phi$-convexity in extremal problems. SIAM J. Control Optim. 16 (1978), 277-300. MR 0479394 | Zbl 0397.46013

[55] S. Dolecki: Semicontinuity in constrained optimization. Part II. Control. Cybernet. 7 (1978), 51-68. MR 0641918 | Zbl 0422.90086

[56] M. Dragomirescu: H-duality. In: Proc. of the 6th Conference on Probability Theory, Brasov, Sept. 1979, (B. Bereanu, Ş. Grigorescu, M. Iosifescu, T. Postelnicu, eds.). Ed. Acad. Rep. Soc. Rom., Bucureşti 1981. MR 0589566 | Zbl 0484.90079

[57] I. Ekeland: Legendre duality in nonconvex optimization and calculus of variations. SIAM J. Control. Optim. 15 (1977), 905-934. MR 0458479 | Zbl 0377.90089

[58] I. Ekeland: Problèmes variationnels non convexes en dualité. C. R. Acad. Sci. Paris, t. 291, Série A-493 (1980). MR 0599991 | Zbl 0448.90063

[59] F. J. Gould: Extensions of Lagrange multiplier functions and duality in nonconvex programming. SIAM J. Appl. Math. 17 (1969), 1280-1297. MR 0263426

[60] H. J. Greensberg, W. P. Pierskalla: Quasiconjugate functions and surrogate duality. Cahiers Centre Études Rech. Oper. 15 (1973), 437-448. MR 0366402

[61] R. Kaltcheva J. V. Outrata Z. Schindler, M. Straškraba: An optimization model for the economic control of reservoir eutrophication. Ecological Modelling 77 (1982), 121-128.

[62] P. Kanniappan: Fenchel-Rockafellar type duality for a non-convex non-differentia! optimization problem. J. Math. Anal. Appl. 97 (1983), 266-276. MR 0721242

[63] F. Lempio, H. Maurer: Differential stability in infinite-dimensional nonlinear programming. Appl. Math. Optim. 6 (1980), 139-152. MR 0563531 | Zbl 0426.90072

[64] H. Maurer, J. Zowe: First and second-order necessary and sufficient optimality conditions for infinite-dimensional programming problems. Math. Programming 16 (1979), 98-110. MR 0517762 | Zbl 0398.90109

[65] O. L. Mangasarian: Unconstrained Lagrangians in nonlinear programming. SIAM J. Control 13 (1975), 772-791. MR 0373626 | Zbl 0269.90045

[66] H. Nakayama H. Sagama, Y. Sawaragi: A generalized Lagrangian dnd multiplier method. J. Optim. Theory Appl. 17 (1975), 211-227. MR 0437056

[67] R. Nehse: Some general separation theorems. Math. Nachr. 84 (1978), 319-327. MR 0518130 | Zbl 0323.46004

[68] R. Nehse: A new concept of separation. Comment. Math. Univ. Carolin. 22 (1981), 169-179. MR 0609945 | Zbl 0518.46005

[69] E. A. Nurminskii: Numerical Methods for the Solution of Deterministic and Stochastic Minimax Problems. (in Russian). Naukova dumka, Kiev 1979. MR 0537769

[70] E. Polak: Computational Methods in Optimization. Academic Press, New York 1971. MR 0282511

[71] D. A. Pierre, M. J. Lowe: Mathematical Programming Via Augmented Lagrangians. Addison-Wesley Publ. Comp., Reading 1975. Zbl 0347.90048

[72] R. T Rockafellar: Augmented Lagrange multiplier functions and duality in nonconvex programming. SIAM J. Control 12 (1974), 268-285. MR 0384163 | Zbl 0257.90046

[73] R. T. Rockafellar: Solving a nonlinear programming problem by way of a dual problem. Symposia Mathematica 19 (1976), 135-160. MR 0446522 | Zbl 0394.90078

[74] S. Rolewicz: On conditions warantying $\phi$-subdifferentiability. Math. Programming Study 14, (1981), 215-224. MR 0600131

[75] Z. Schindler: Multiplier Methods in Discrete-Time Optimal Control. (in Czech). Ph.D. Thesis, Prague 1980.

[76] I. Singer: A Fenchel-Rockafellar type duality theorem for maximization. Bull. Austral. Math. Soc. 20 (1979), 193-198. MR 0557226 | Zbl 0404.90101

[77] I. Singer: Some new applications of the Fenchel-Rockafellar duality theorem: Lagrange multipliers theorems and hyperplane theorems for convex optimization and best approximation. Nonlinear Analysis 3 (1979) 2, 239-248. MR 0525974

[78] R. Temam: Nouvelles applications de la dualité en calcul des variations. Analyse Convexe et Ses Applications, Comptes Rendus, Janvier 1974. Springer-Verlag, Berlin 1974. MR 0482469

[79] A. P. Wierzbicki, A. Hatko: Computational methods in Hilbert space for optimal control problems with delays. In: Proc. of 5th IFIP Conf. on Optimization Techniques, Rome (R. Conti, A. Ruberti, eds.). L. N. in Comp. Sci., Vol. 3, Springer-Verlag, Berlin 1973. MR 0448218 | Zbl 0289.49030

[80] E. H. Zarantonello: Projections on convex sets in Hilbert space and spectral theory. In: Contributions to Nonlinear Functional Analysis (E. H. Zarantonello, ed.). Academic Press, New York 1971. Zbl 0281.47043

[81] J. L. Lions, E. Magenes: Problèmes aux limites non-homogénes et applications. Dunod, Paris 1968. Zbl 0165.10801

[82] A.D. Ioffeand V. M. Tichomirov: Extensions of variational problems. Trans. Moscow Math. Soc. 18 (1968), 207-273.

[83] J. P. Aubin: Gradients généralisés de Clarke. Ann. Sci. Math. Québec II (1978), 2, 197-252. MR 0516562 | Zbl 0411.49001

[84] A. Auslender: Differentiable stability in non-convex and non-differentiable programming. Math. Programming Study 10 (1979), 29-41. MR 0527055 | Zbl 0403.90068

[85] J. M. Borwein: Semi-infinite programming duality: how special is it?. In: Semi-infinite Programming and Applications. (Proc. of a conference, A. V. Fiacco, K. O. Kortanek, Eds.). L. N. in Econom. and Math. Systems, Vol. 215, Springer-Verlag, Berlin 1983. MR 0709266 | Zbl 0514.49019

[86] F. H. Clarke: Generalized gradients and applications. Trans. Amer. Math. Soc. 205 (1975), 247-262. MR 0367131 | Zbl 0307.26012

[87] F. H. Clarke: Generalized Gradients of Lipschitz Functionals. MRC Technical Summary Report # 1687, University of Wisconsin-Madison 1976.

[88] F. H. Clarke: A new approach to Lagrange multipliers. Math. Oper. Res. 1 (1976), 165-174. MR 0414104 | Zbl 0404.90100

[89] F. H. Clarke: Optimization and Nonsmooth Analysis. J. Wiley and Sons, New York 1983. MR 0709590 | Zbl 0582.49001

[90] V. F. Demyanov: Nondifferentiable Optimization. (in Russian). Nauka, Moscow 1981. MR 0673171

[91] J. Gauvin: The generalized gradient of a marginal function in mathematical programming. Math. Oper. Res. 4 (1979), 458-463. MR 0549132 | Zbl 0433.90075

[92] J.-B. Hiriart Urruty: New concepts in nondifferentiable programming. Bull. Soc. Math. France, Mem. 60 (1979), 57-85. MR 0562256 | Zbl 0469.90071

[93] A. D. Ioffe V. M. Tichomirov: Theory of Extremal Problems. (in Russian). Nauka, Moscow 1974. MR 0410502

[94] A. D. Ioffe: Necessary and sufficient conditions for a local minimum. (3 parts). SIAM J. Control. Optimiz. 17 (1979), 245-265. MR 0525025 | Zbl 0417.49029

[95] O. A. Ladyzhenskaya V. A. Solonnikov, N. N. Uralceva: Linear and Quasilinear Equations of the Parabolic Type. (in Russian). Nauka, Moscow 1967.

[96] CI. Lemaréchal J. J. Strodiot, A. Bihain: On a Bundle Algorithm for Nonsmooth Optimization. NPS 4, Madison 1980.

[97] O. L. Mangasarian, S. Fromowitz: The Fritz John necessary optimality conditions in the presence of equality and inequality constraints. J. Math. Anal. Appl. 17(1967), 37-47. MR 0207448

[98] R. Mifflin: Semismooth and semiconvex functions in optimization. SIAM J. Control Optimiz. 15 (1977), 959-972. MR 0461556

[99] J. Nečas: Introduction to the Theory of Nonlinear Elliptic Equations. Teubner Texte zur Math., Band 52, Teubner Verlag, Leipzig 1983. MR 0731261

[100] J. Nečas, I. Hlaváček: Mathematical Theory of Elastic and Elasto-Plastic Bodies. An Introduction. Elsevier, Amsterdam -Oxford-New York 1981. MR 0600655

[101] J. V. Outrata: On a class of nonsmooth optimal control problems. Appl. Math. Optim. 10 (1983), 287-306. MR 0713480 | Zbl 0524.49021

[102] J. V. Outrata, Z. Schindler: On some nondifferentiable problems in optimal control. Prep. of the IIASA Workshop "Nondifferentiable optimization: Motivations and Applications" held at Sopron, September 1984. MR 0822009

[103] J. V. Outrata, J. Jarušek: Exact penalties with Sobolev norms in optimal control. Proc. of the Workshop "Mathematical Programming - Theory and Applications" held at Wartburg, November 1984.

[104] T. Pietrzykowski: The potential method for conditional maxima in the locally compact metric spaces. Numer. Math. 14 (1970), 4, 325-329. MR 0256730 | Zbl 0195.46304

[105] J. C. Pomerol: The Lagrange multiplier set and the generalized gradient set of the marginal function of a differentiable program in a Banach space. J. Optim. Theory Appl. 38 (1982), 307-317. MR 0686209 | Zbl 0472.90077

[106] R. T. Rockafellar: The Theory of Subgradients and Its Applications to Problems of Optimization: Convex and Nonconvex Functions. Helderman Verlag, Berlin 1981. MR 0623763 | Zbl 0462.90052

[107] T. I. Sivelina: The minimization of one kind of quasidifferentiable functions. (in Russian). Vestnik LGU (1983), 7, 103-105. MR 0702639

[108] Z. Schindler: Optimal control of the eutrophisation in water reservoirs. (in Czech). Vodohosp. Časopis 30 (1982), 5, 536-548.

[109] R. H. Smith: Multiplier Functionals for Programming in Normed Spaces. Ph.D. Thesis, Johns Hopkins Univ., Baltimore 1971.

[110] R. H. Smith, V. D. VandeLinde: A saddle-point optimality criterion for nonconvex programming in normed spaces. SIAM J. Appl. Math. 23 (1972), 2, 203-213. MR 0317778

[111] L. Thibault: Sur les fonctions compactement lipschitziennes et leurs applications: programmation mathématique, controle optimal, espérance conditionnele. Thèses, Montpellier 1980.

[112] J.-B. Hiriart Urruty: Gradients généralisés de fonctions marginales. SIAM J. Control Optimiz. 16 (1978), 301-316. MR 0493610 | Zbl 0385.90099

[113] S. Agmon A. Douglis, L Nirenberg: Estimates near boundary for solutions of elliptic partial differential equations satisfying general boundary conditions. Part II. Comm. Pure Appl. Math. 17 (1964), 35-92. MR 0162050

[114] J. A. Nelder, R. Mead: A simplex method for function minimization. Computer J. 7 (1965), 4, 308-313. Zbl 0229.65053

[115] V. F. Demyanov S. Gamidov, T. I. Sivelina: An algorithm for minimizing a certain class of quasidifferentiable functions. NASA Working Paper WP-83-122.

[116] R. E. Burkard: Methoden der ganzzähligen Optimierung. Springer-Verlag, Berlin-Heidelberg-New York 1972. MR 0342175

[117] W. I. Zangwill: Non-linear programming via penalty functions. Management Sci. 13 (1967), 344-358. MR 0252040 | Zbl 0171.18202