Cox, S. J., and E. Flikkema. “The Minimal Perimeter for $N$ Confined Deformable Bubbles of Equal Area”. The Electronic Journal of Combinatorics 17, no. 1 (March 22, 2010): R45. Accessed March 17, 2026. https://www.combinatorics.org/ojs/index.php/eljc/article/view/v17i1r45.