Eigenvalue asymptotics for weighted polyharmonic operator with a singular measure in the critical case

e find that, in the critical case $2l={\mathbf N}$, the eigenvalues of the problem $\lambda(-\Delta)^{l}u=Pu$ with the singular measure $P$ supported on a compact Lipschitz surface of an arbitrary dimension in $\R^{\Nb}$ satisfy an asymptotic formula of the same order as in the case of an absolutely continuous measure.