1. The problem of knowledge;Ayer,1956
2. Bentley, J. (Forthcoming). ‘Conceptions of protocol statements in Neurath and Carnap’ in Christian Damböck, J. Friedl, U. Höfer (eds.), Ways of the scientific world-conception. Rudolf Carnap and Otto Neurath. Boston: Brill Rodopi.
3. The logical structure of the world and pseudoproblems in philosophy;Carnap,1928
4. Psychology in physical language;Carnap,1932
5. ‘Über Protokollsätze’, Erkenntnis 3, pp. 215–28; trans. R. Creath and R. Nollan as ‘On Protocol Sentences’, Nous 21 (1987);Carnap,1932