equations and linear elasticity have always a constructive aim: for example, the results of paper , which deals with the asymptotic analysis of the potential, were included in the book and led to the definition of the Fichera corner problem as a standard benchmark problem for numerical methods. Another example of his work on quantitative problems is the interdisciplinary study , surveyed in , where methods of mathematical analysis and numerical analysis are applied to a problem posed by biological sciences. History of mathematics his work in this field occupy all the volume . He wrote bibliographical sketches for a number of mathematicians, both teachers, friends and collaborators, including Mauro Picone, Luigi Fantappiè, Pia Nalli, Maria Adelaide Sneider, Renato Caccioppoli, Solomon Mikhlin, Francesco Tricomi, Alexander Weinstein, Aldo Ghizzetti. His historical works contain several observations against the so-called historical revisitation: the meaning of this concept is clearly stated in the paper . He identifies with the word revisitation the analysis of historical facts basing only on modern conceptions and points of view: this kind of analysis differs from the "true" historical one since it is heavily affected by the historian's point of view. The historian applying this kind of methodology to history of mathematics, and more generally to the history of science, emphasizes the sources that have led a field to its modern shape, neglecting the efforts of the pioneers. Selected publications A selection of Gaetano Fichera's works was published respectively by the Unione Matematica Italiana and the Accademia Pontaniana in his "opere scelte" and in the volume . These two references include most of the papers listed in this section: however, these volumes does not include his monographs and textbooks, as well as several survey papers on various topic pertaining to his fields of research. Papers Research papers . In this article, Fichera proves a necessary and sufficient condition for the exchange of the limit and the integration operations for sequences of functions, in the spirit of Henri Lebesgue's Dominated convergence theorem (which, however states only a sufficient condition). . A classical paper in potential theory. . In this paper, Gaetano Fichera gives the first proofs of existence and uniqueness theorems for the mixed boundary value problem involving a general second order selfadjoint elliptic operators in fairly general domains. . This paper is an important contribution to measure theory: the Radon–Nikodym theorem is extended in order to include singular finitely