 A delightful, accessible and authoritative introduction to intuitionistic mathematics and logic is Wim Veldman’s [2021]. The third edition [1971] of Heyting’s classic [1956] is an attractive introduction to intuitionistic philosophy, logic and mathematical practice. As part of the formidable project of editing and publishing Brouwer’s Nachlass, van Dalen [1981] provides a comprehensive view of Brouwer’s own intuitionistic philosophy. The English translation, in van Heijenoort [1969], of Brouwer’s [1927] (with a fine introduction by Parsons) is still an indispensable reference for Brouwer’s theory of the continuum. Veldman [1990] and [2005] are authentic modern examples of traditional intuitionistic mathematical practice. Troelstra [1991] places intuitionistic logic in its historical context as the common foundation of constructive mathematics in the twentieth century. Bezhanishvili and de Jongh [2005, Other Internet Resources] includes recent developments in intuitionistic logic.