Full context:   The four stages appeared in the 1960 textbook Management of Training Programs by three management professors at New York University. Management trainer Martin M. Broadwell called the model "the four levels of teaching" in an article published in February 1969. Paul R. Curtiss and Phillip W. Warren mentioned the model in their 1973 book The Dynamics of Life Skills Coaching. The model was used at Gordon Training International by its employee Noel Burch in the 1970s; there it was called the "four stages for learning any new skill". Later the model was frequently attributed to Abraham Maslow, incorrectly since the model does not appear in his major works.