More recommended reading

Masculine and Feminine: The Natural Flow of Opposites in the Psyche by Gareth S. Hill

A book, written from a Jungian perspective, that gives insight into how the masculine and feminine exists in all people, not only men or women. It explains how the masculine and feminine play a part in all our lives. Information about the book can be found here https://www.goodreads.com/book/show/226926.Masculine_and_Feminine.

Sentence completion assessments for ego development, meaning-making, and wisdom maturity, including STAGES

An extensive article with some interesting background information on sentence completion based methods (such as the SCT used by Greuter), and a whole bunch of other information that cannot be captured in a single sentence. See here: http://integralleadershipreview.com/15642-sentence-completion-assessments-for-ego-development-meaning-making-and-wisdom-maturity-including-stages-overview-and-summary-this-article-began-as-a-series-of-short-white-papers-providing-various/ or for PDF version (which I found much later) which is nicer to read http://www.perspegrity.com/papers/STAGES%20background_Murray.pdf

Individuation process

The process of individuation is one of the greater gifts Carl Jung left the world, you can read about it here: https://scottjeffrey.com/individuation-process-jungian-psychology/ Beware that that there are some "ads" that try to sell you self improvement material, but the summary is otherwise sound.

Evolving consciousness in leaders: promoting late-stage conventional and post-conventional development by Nicola Caroline Vincent

https://digital.library.adelaide.edu.au/dspace/bitstream/2440/87864/8/02whole.pdf

Leadershipship Maturity Framework: Stage Descriptions

https://www.madstonblack.com.sg/wp-content/uploads/2016/05/Cook-Greuter-maturity-stages.pdf

Higher stages of human development

http://031ee85.netsolhost.com/images/Journal_11-2_Higher_Development.pdf

Cook-Greuter: Construct Aware Stage and the Fool Archetype

https://integral-review.org/issues/vol_14_no_1_cook-greuter_construct_aware_stage_and_the_fool_archetype.pdf

Consciousness quotient: CQ-i

Some interesting questions that in my experience serve as a reality check where you stand. The questions themselves sometimes more valuable than the answers you give. http://www.consciousness-quotient.com/what-is-the-cqi/ and http://www.consciousness-quotient.com/test-cq/

Vertical leadership development

Some whitepapers on key ingredients to leadership development: https://www.ccl.org/wp-content/uploads/2015/04/VerticalLeadersPart1.pdf and https://www.ccl.org/wp-content/uploads/2015/04/verticalLeadersPart2.pdf

Related whitepapers: https://www.ccl.org/wp-content/uploads/2015/04/TYO.pdf and https://www.ccl.org/wp-content/uploads/2018/11/how-to-know-if-your-culture-change-strategy-is-working-white-paper.pdf

The psychology of the quiet ego

https://pdfs.semanticscholar.org/7f11/6808e71345f8a0a00a514fe839849beb37f4.pdf

Leadership agility

A book that is based on vertical development stage theory like the work of Greuter, but really focusing on the topic of leadership: https://www.researchgate.net/publication/23318406_Leadership_agility

The hidden talent: Ten ways to identify and retain transformational leaders

https://osca.co/publications/the-hidden-talent-ten-ways-to-identify-and-retain-transformational-leaders/

The anti-hero: The hidden revolution in leadership & change

https://osca.co/publications/anti-hero-the-hidden-revolution-in-leadership-change/

Fostering post‐conventional consciousness in leaders:why and how?

https://gripa.uqam.ca/wp-content/uploads/2018/09/02621711111126828.pdf

Late stages of adult development: One Linear Sequence or Several Parallel Branches?

https://integral-review.org/issues/vol_14_no_1_jordan_late_stages_of_adult_development.pdf

Shapes of Mind: The 10 Stages of Consciousness

https://integrallife.com/ten-stages-consciousness/