Did John Holland take the Self-Directed Search? What do you think is John Holland's code?
To find the answer to these questions and more, read:
My Life with a Theory: John L. Holland's Autobiography and Theory of Careers
In 1959, John L. Holland introduced a theory of vocational choices involving personality typology (widely known in the career development field as the Holland Code, or RIASEC). Included with this previously unpublished autobiography are book chapters, journal articles and other original source material that will enhance the reader's understanding of both the theory and the scientist. Jack R. Rayman & Gary D. Gottfredson, Editors (2020).