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Contractor directions, directional contractors and directional contractions for solving equations. Pacific J. Math. 62 (1976), 1-18. 
MR 0473939 | 
Zbl 0352.47027[2] M. ALTMAN: 
An application of the method of contractor directions to nonlinear programming. Numer. Funct. Anal. and Optim. 1 (1979), 647-663. 
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A general principle on ordered sets in nonlinear functional analysis. Adv. in Math. 21 (1976), 355-364. 
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On a lemma of Bishop and Phelps. Pacific J. Math. 55 (1974), 335-341. 
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Fixed points and partial orders. Proc. Amer. Math. Soc. 60 (1976), 365-366. 
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Common fixed points and partial orders. Proc. Amer. Math. Soc. 77 (1979), 365-368. 
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Normal solvability and the Fredholm alternative for mappings into infinite dimensional manifolds. J. Funct. Anal. 8 (1971), 250-274. 
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Zbl 0228.47044[9] F. E. BROWDER: 
On a theorem of Caristi and Kirk. Fixed Point Theory and its Applications, pp. 23-27, Academic Press, New York, 1976. 
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Zbl 0379.54016[10] J. CARISTI: 
Fixed point theorems for mappings satisfying inwardness conditions.  Trans. Amer. Math. Soc. 215 (1976), 241-251. 
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Zbl 0305.47029[11] W. J. CRAMER W. O. RAY: 
Solvability of nonlinear operator equations. Pacific J. Math. 95 (1981), 37-50. 
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A geometric theorem useful in nonlinear functional analysis. Boll. Un. Mat. Ital. 6 (1972), 369-375. 
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A generalization of Caristi's theorem with applications to nonlinear mapping theory. Pacific J. Math. 69 (1977), 339-346. 
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Sur les problèmes variationals. C.R. Acad. Sci. Paris, 275 (1972), 1057-1059. 
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Nonconvex minimization problems. Bull. Amer. Math. Soc., N.S. 1 (1979), 443-474. 
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Zbl 0441.49011[17] R. B. HOLMES: 
Geometric functional analysis and its applications. Springer Verlag, New York, 1975. 
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Zbl 0336.46001[18] S. KASAHARA: 
On fixed points in partially ordered sets and Kirk-Caristi theorem. Math. Sem. Notes Kobe Univ. 3 (1975), 229-232. 
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Zbl 0341.54056[19] W. A. KIRK: 
Caristi's fixed point theorem and metric convexity. Colloq. Math. 36 (1976), 81-86. 
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Zbl 0353.53041[20] W. A. KIRK J. CARISTI: 
Mapping theorems in metric and Banach spaces. Bull. Acad. Pol. Sci. 23 (1975), 891-894. 
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A short proof of the Caristi theorem. Comment. Math. 20 (1977/78), 427-428. 
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A new proof of Caristi's fixed point theorem. Proc. Amer. Math. Soc. 66 (1977), 54-56. 
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Zbl 0369.54022[25] M. TURINICI: 
Maximal elements in partially ordered topological spaces and applications. An. St. Univ. "Al. I. Cuza" Iasi, 24 (1978), 259-264. 
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Function lipschitzian mappings on convex metric spaces. Comment. Math. Univ. Carolinae 22 (1981), 289-303. 
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Zbl 0497.54010[27] M. TURINICI: 
Local and global lipschitzian mappings on ordered metric spaces. Math. Nachrichten, to appear. 
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Zbl 0481.54008[28] M. TURINICI: 
Mapping theorems via variable drops in Banach spaces. Rend. Ist. Lombardo, to appear. 
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Zbl 0504.46008[29] C. URSESCU: 
Sur le contingent dans les espaces de Banach. Proc. Inst. Math. Iasi, pp. 183-184, Ed. Acad. RSR, Bucuresti, 1976. 
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Zbl 0372.46019[30] C. S. WONG: 
On a fixed point theorem of contractive type. Proc. Amer. Math. Soc. 57 (1976), 283-284. 
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Zbl 0329.54042[31] P. P. ZABREDCO M. A. KRASNOSELSKII: 
Solvability of nonlinear operator equations. (Russian), Funkc. Analiz i ego Prilož. 5 (1971), 42-44. 
MR 0283646