The art of thought / Graham Wallas. Wallas, Graham, 1858-1932. Phychology 150 WAA London : Watts, 1945. 1945. 1945 Text xii, 162 p. ; eng Also available online http://nla.gov.au/nla.obj-502468959 http://nla.gov.au/nla.obj-502468959 Also available online http://nla.gov.au/nla.obj-502468959 http://nla.gov.au/nla.obj-502468959