1. 1. For all of Fleck's quotations see the bibliography of Fleck's publications in the appendix to this volume (pp. 445-457). A complete bibliography of Twardowski's works is given in Gromska (1938)
2. 2. of Ajdukiewicz's in Czeżowski (1964) (againin Ajdukiewicz (1960/65), in English in Ajdukiewicz (1978) and of Chwistek's in Estreicher (1971). Further literature on Polish philosophy is given in Schnelle (1982).
3. Ajdukiewicz, Kazimierz: 1934a, ‘Language and Meaning’ (first published in German as’ Sprache und Sinn’, in Erkenntnis 4 (1934), 100–138), in: Ajdukiewicz (1978), 35-60.
4. Ajdukiewicz, Kazimierz: 1934b, ‘The World-Perspective and the Conceptual Apparatus’ (first published in German as ‘Das Weltbild und die Begriffsapparatur’, in Erkenntnis 4 (1934), 259–287), in: Ajdukiewicz (1978), 67-89.
5. Ajdukiewicz, Kazimierz: 1934c, ‘The Scientific World-Perspective’ (first published in German as ‘Die Wissenschaftliche Weltperspektive’, in Erkenntnis 5 (1935), 22–30), in: Ajdukiewicz (1978), 111-117.