The research behind this format. This is not a reading list. These are the studies behind how the circles are set up.
Fay, N., Garrod, S., Carletta, J. (2000). Group discussion as interactive dialogue or as serial monologue: the influence of group size. Psychological Science, 11(6), 481-486. doi.org/10.1111/1467-9280.00292
Tuckman, B. W. (1965). Developmental sequence in small groups. Psychological Bulletin, 63(6), 384-399. doi.org/10.1037/h0022100
Tuckman, B. W., Jensen, M. A. C. (1977). Stages of small-group development revisited. Group & Organization Studies, 2(4), 419-427. doi.org/10.1177/105960117700200404
Swift, J. K., Greenberg, R. P. (2012). Premature discontinuation in adult psychotherapy: a meta-analysis. Journal of Consulting and Clinical Psychology, 80(4), 547-559. doi.org/10.1037/a0028226