M. Mansur, Abdalla et C. Offin, Daniel, A minimizing property of homographic solutions, Acta mathematica Sinica. English series (Print) , 30(2), 2014, pp. 353-360
In this paper, we prove that the homographic solutions to the rhombus four body problem are the variational minimizers of the Lagrangian action restricted on a holonomically constrained rhombus loop space.