Conrad, K. (1954). New problems of aphasia. Brain, 77(4), 491-509. doi:10.1093/brain/77.4.491. [FULLTEXT]
A History of Psycholinguistics
Bibliography for Levelt (2013)

Conrad, K. (1954). New problems of aphasia. Brain, 77(4), 491-509. doi:10.1093/brain/77.4.491. [FULLTEXT]