Dirichlet eigenfunctions of the square membrane: Courant's property, and   A. Stern's and {\AA}. Pleijel's analyses
  In this paper, we revisit Courant's nodal domain theorem for the Dirichlet eigenfunctions of a square membrane, and the analyses of A. Stern and {\AA}. Pleijel. 
Pierre B\'erard (IF), Bernard Helffer (LM-Orsay, LMJL)
math.AP math.SP