V. PTÁK: Deux théorèmes de factorisation
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 V. PTÁK: A theorem of the closed graph type
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 V. PTÁK: A quantitative refinement of the closed graph theorem
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 V. PTÁK: Nondiscrete mathematical induction and iterative existence proofs. Linear Algebra and its Applications (in print).
 V. PTÁK: The rate of convergence of Newton's method. Numerische Mathematik (in print).
 V. PTÁK: A rate of convergence. Abh. aus dem Math. Seminar Hamburg (in print).